JP2023117324A - Recording paper, method for manufacturing the same, adhesive label and in-mold label - Google Patents

Abstract

To provide recording paper which can reduce environmental loads, has high adhesion, especially, water-resistant adhesion, prevents ink transition failures of a printed matter and lowering of ink adhesion force, and prevents blocking and a change in paper quality after printing.SOLUTION: Recording paper has a laminated resin film having a base material and a ground layer composed of a thermoplastic resin composition, and a resin film on the ground layer. The indentation elastic modulus of the ground layer is 50-1,200 MPa, and the content of the inorganic filler in the base material exceeds 45 mass% and is 80 mass% or less. The resin film contains a resin that is a reactant of a cationic water-soluble polymer and a silane coupling agent, and the content of a silane coupling agent component with respect to 100 pts.mass of the cationic water-soluble polymer component is 15-60 pts.mass. Thermoplastic resin particles are not contained in the resin film, and the content of the inorganic filler with respect to 100 pts.mass of the cationic water-soluble polymer component is 9 pts.mass or less.SELECTED DRAWING: Figure 1

Description

TECHNICAL FIELD The present invention relates to a recording paper, a manufacturing method thereof, an adhesive label and an in-mold label.

Conventionally, various recording papers such as printing paper, poster paper, label paper, inkjet recording paper, thermal recording paper, thermal transfer receiving paper, pressure-sensitive transfer recording paper, and electrophotographic recording paper have been used for water resistance, weather resistance and durability. A superior recording paper has been proposed. For example, thermal transfer recording paper having a resin film formed by applying a coating liquid containing an olefin copolymer emulsion and drying it in order to improve water resistance and stabilize the coating film of the recording layer. has been proposed (see, for example, Patent Document 1).

A similar resin film is also applied to recording paper suitable for other recording methods, for example, it has been proposed as a recording paper suitable for wet electrophotographic printing using liquid toner, which has become popular in recent years. (See Patent Document 2, for example). In this recording paper, the emulsion-derived olefinic copolymer particles in the surface treatment layer are softened by heating and fused with the liquid toner, thereby enhancing adhesion to the liquid toner and the substrate. .

On the other hand, as a label for a plastic container, an adhesive film having an adhesive layer provided on the back surface of a thermoplastic resin film and an in-mold label have been proposed (see, for example, Patent Documents 3 and 4).

For example, a heat-sealing layer that is heat-sealed to the resin container is provided on the base layer, and the heat-sealing layer softens and melts at the product temperature or mold temperature of the preform during biaxial stretch blow molding, There has been proposed an in-mold label that is adhered to the surface of an axially-stretched blow-molded product so that the label can be positioned accurately and the adhesiveness to the molded product is enhanced.

An in-mold label is usually provided with a printed layer by printing letters, designs, or the like on the surface of the substrate opposite to the heat-seal layer.

JP-A-2002-113959 WO2014/092142 JP 2017-159651 A JP-A-2004-136486

Although the resin coating made of the emulsion-based thermoplastic resin composition described in Patent Document 1 or 2 has improved water resistance, there is still room for improvement in terms of adhesion between the substrate surface and the resin coating. found. In addition, the emulsion-derived olefinic copolymer particles are fused together by heat, and the surface shape of the resin film is likely to be deformed. Therefore, in addition to the anti-blocking property when printing paper is stored at high temperatures, there is room for improvement in terms of the change in glossiness of the printed surface before and after printing in printing methods such as UV curing or heat fixing, or before and after in-mold molding. It turned out that there is

If the adhesion strength between the base material and the resin coating is not sufficient, problems such as adhesive residue may occur when an adhesive layer is provided on the recording paper having the resin coating described in Patent Document 1 or 2 above to prepare an adhesive film. It was found that there is room for improvement.
In addition, from the viewpoint of reducing the environmental load, there is a demand for reduction of plastic waste.

The present invention can reduce the environmental load, has high adhesion, especially water-resistant adhesion, less ink transfer failure and lower ink adhesion on printed matter, less blocking, and improved paper quality after printing and molding. An object of the present invention is to provide a recording paper that hardly changes, a method for manufacturing the same, an adhesive label, and an in-mold label.

The present invention is as follows.
[1] A laminated resin film having a substrate made of a thermoplastic resin film and an underlying layer made of a thermoplastic resin composition disposed on at least one surface of the substrate, and the underlying layer of the laminated resin film A recording paper having a resin coating arranged facing each other,
The indentation elastic modulus of the underlayer is 50 to 1200 MPa,
The base material contains an inorganic filler, and the content of the inorganic filler in the base material is more than 45% by mass and 80% by mass or less,
The resin coating contains a resin that is a reaction product of a cationic water-soluble polymer and a silane coupling agent,
The content of the silane coupling agent component with respect to 100 parts by mass of the cationic water-soluble polymer component in the resin film is 15 to 60 parts by mass,
The resin coating contains no thermoplastic resin particles,
A recording paper, wherein the content of the inorganic filler is 9 parts by mass or less per 100 parts by mass of the cationic water-soluble polymer component in the resin coating.

[2] The recording paper according to [1] above, wherein the cationic water-soluble polymer is a (meth)acrylic polymer or an ethyleneimine polymer having an amino group or an ammonium salt structure.

[3] The (meth)acrylic polymer or ethyleneimine polymer having an amino group or an ammonium salt structure has a primary to tertiary amino group or a primary to tertiary ammonium salt structure. The recording paper according to [2] above, characterized in that:

[4] The recording paper according to any one of [1] to [3], wherein the silane coupling agent is an epoxy silane coupling agent.

[5] The recording paper according to any one of [1] to [4], wherein the resin coating has a thickness of 0.01 to 5 μm.

[6] A method for producing a recording paper having a resin coating on a laminated resin film,
The laminated resin film has a substrate made of a thermoplastic resin film and a base layer made of a thermoplastic resin composition disposed on at least one surface of the substrate,
The indentation elastic modulus of the underlayer is 50 to 1200 MPa,
The base material contains an inorganic filler, and the content of the inorganic filler in the base material is more than 45% by mass and 80% by mass or less,
An aqueous solution containing a cationic water-soluble polymer and a silane coupling agent, containing no thermoplastic resin particles, and having an inorganic filler content of 9 parts by mass or less with respect to 100 parts by mass of the cationic water-soluble polymer. A method for producing a recording paper, characterized in that the resin film is formed on the laminated resin film by coating on the underlayer and then drying.

[7] A substrate made of a thermoplastic resin film, a first underlayer made of a thermoplastic resin composition arranged on one side of the substrate, and a thermoplastic resin composition arranged on the other side of the substrate A laminated resin film having a second base layer made of
a resin coating disposed facing the first underlayer of the laminated resin film;
and a resin coating disposed facing the second underlayer of the laminated resin film; An adhesive label having an adhesive layer that
The indentation elastic modulus of the first underlayer and the second underlayer is 50 to 1200 MPa,
The base material contains an inorganic filler, and the content of the inorganic filler in the base material is more than 45% by mass and 80% by mass or less,
The resin coating contains a resin that is a reaction product of a cationic water-soluble polymer and a silane coupling agent,
The content of the silane coupling agent component with respect to 100 parts by mass of the cationic water-soluble polymer component in the resin film is 15 to 60 parts by mass,
The resin coating contains no thermoplastic resin particles,
A pressure-sensitive adhesive label, wherein the content of the inorganic filler is 9 parts by mass or less with respect to 100 parts by mass of the cationic water-soluble polymer component in the resin coating.

[8] An in-mold label in which a heat seal layer is provided on one surface of a laminated resin film,
Having a resin coating provided on the surface opposite to the heat seal layer of the laminated resin film,
The laminated resin film has a substrate made of a thermoplastic resin film, and a base layer made of a thermoplastic resin composition provided between the substrate and the resin coating,
The indentation elastic modulus of the underlayer is 50 to 1200 MPa,
The base material contains an inorganic filler, and the content of the inorganic filler in the base material is more than 45% by mass and 80% by mass or less,
The resin coating contains a resin that is a reaction product of a cationic water-soluble polymer and a silane coupling agent,
The content of the silane coupling agent component with respect to 100 parts by mass of the cationic water-soluble polymer component in the resin film is 15 to 60 parts by mass,
The resin coating contains no thermoplastic resin particles,
An in-mold label, wherein the content of the inorganic filler is 9 parts by mass or less with respect to 100 parts by mass of the cationic water-soluble polymer component in the resin coating.

[9] further comprising a resin coating provided on a surface of the heat seal layer opposite to the laminated resin film;
The resin coating contains a resin that is a reaction product of a cationic water-soluble polymer and a silane coupling agent,
The content of the silane coupling agent component with respect to 100 parts by mass of the cationic water-soluble polymer component in the resin film is 15 to 60 parts by mass,
The resin coating contains no thermoplastic resin particles,
The in-mold label according to the above [8], wherein the content of the inorganic filler with respect to 100 parts by mass of the cationic water-soluble polymer component in the resin coating is 9 parts by mass or less.

According to the present invention, it is possible to reduce the environmental load, the adhesion, especially the water-resistant adhesion, is high, the ink transfer failure of the printed matter and the decrease in the ink adhesion are small, the blocking is small, and the paper quality after printing and molding is achieved. It is possible to provide a recording paper, an adhesive label, an in-mold label, and a method for manufacturing a recording paper with little change.

1 is a cross-sectional view showing the structure of a recording sheet according to one embodiment of the present invention; FIG. 1 is a cross-sectional view showing the structure of an adhesive label according to one embodiment of the present invention; FIG. 1 is a cross-sectional view showing a configuration example of an in-mold label according to one embodiment of the present invention; FIG. FIG. 4 is a cross-sectional view showing another configuration example of the in-mold label according to one embodiment of the present invention; 4 is a photograph of the surface of the resin coating of the recording paper of Comparative Example 1-3. 4 is a photograph of the surface of the resin coating of the recording paper of Example 1-1.

The recording paper, the method for producing the same, the adhesive label and the in-mold label of the present invention are described in detail below. The following description is one embodiment of the present invention, and the present invention is not limited thereto.
In the following description, the description of "(meth)acrylic" indicates both acrylic and methacrylic. The description of "(co)polymer" indicates both homopolymers and copolymers.

(Recording sheet)
The recording paper of the present invention includes a laminated resin film and a resin coating disposed on at least one surface of the laminated resin film.
The laminated resin film has a substrate made of a thermoplastic resin film, and a base layer made of a thermoplastic resin composition disposed on at least one surface of the substrate.

FIG. 1 shows a configuration example of recording paper as one embodiment of the present invention.
As shown in FIG. 1, the recording paper 10 comprises a laminated resin film 101 having a substrate 1 and an underlying layer 2 made of a thermoplastic resin composition located on one side of the substrate 1 .
Further, the recording paper 10 has a resin coating 3 arranged facing the base layer 2 of the laminated resin film 101 .

In this specification, the laminated resin film and the resin coating applied to at least one surface of the laminated resin film are collectively referred to as recording paper. Specifically, in FIG. 1, a laminated body composed of the resin coating 3 and the laminated resin film 101 (including the base layer 2 and the base material 1) is referred to as the recording paper 10. As shown in FIG.

<Laminated resin film>
The laminated resin film has a substrate made of a thermoplastic resin film, and a base layer made of a thermoplastic resin composition disposed on at least one surface of the substrate.

<<Base material>>
In the present invention, the base material consists of a thermoplastic resin film. By using a thermoplastic resin film as a substrate, mechanical strength such as stiffness, water resistance, chemical resistance, and optionally opacity can be imparted to recording paper or printed matter using recording paper.

<<<thermoplastic resin>>>
The thermoplastic resin used for the substrate is not particularly limited, and examples thereof include polyethylene resins, polypropylene resins, polybutene, polyolefin resins such as 4-methyl-1-pentene (co)polymer; ethylene-vinyl acetate copolymer; coalescence, ethylene-(meth)acrylic acid copolymer, ethylene-(meth)acrylic acid copolymer metal salt (ionomer), ethylene-(meth)acrylic acid alkyl ester copolymer (the number of carbon atoms in the alkyl group is 1 8), functional group-containing olefin resins such as maleic acid-modified polyethylene and maleic acid-modified polypropylene; aromatic polyesters (polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, etc.), aliphatic polyesters (polybutylene succinate, polylactic acid, etc.); polyamide resins such as nylon-6, nylon-6,6, nylon-6,10, nylon-6,12; syndiotactic polystyrene, atactic polystyrene, acrylonitrile - Styrene-based resins such as styrene (AS) copolymers, styrene-butadiene (SBR) copolymers, acrylonitrile-butadiene-styrene (ABS) copolymers; polyvinyl chloride resins; polycarbonate resins; . These resins can be used in combination of two or more.

Among them, polyolefin-based resins and polyester-based resins are preferable because they have high water resistance and transparency and are easy to form a resin film, which will be described later. From the viewpoint of film formability, among polyolefin resins, polypropylene resins are more preferable, and among polyester resins, polyethylene terephthalate is more preferable. The effect of the present invention is remarkable when polyolefin resin is used.

Examples of polypropylene-based resins include isotactic homopolypropylene and syndiotactic homopolypropylene obtained by homopolymerizing propylene, and ethylene, 1-butene, 1-pentene, 1-hexene, 4-methyl- Polypropylene-based copolymers having various stereoregularities obtained by copolymerizing α-olefins such as 1-pentene, 1-heptene, and 1-octene can be used. The polypropylene-based copolymer may be a two-component system or a multi-component system of three or more components, and may be a random copolymer or a block copolymer.

<<<Filler>>>
In the present invention, the substrate contains an inorganic filler. The content of the inorganic filler in the substrate is more than 45% by mass and 80% by mass or less. By including an inorganic filler in the base material, it is possible to adjust the rigidity, whiteness and opacity of the base material. In addition, since the content of the inorganic filler is as high as more than 45% by mass, it is possible to reduce the amount of resin used and to impart appropriate roughness to the surface of the base material and the base layer of the resin coating described later. It is possible to provide a recording sheet in which the adhesiveness between the underlayer and the resin film is improved and, accordingly, the ink adhesiveness is less reduced.

When a base material containing an inorganic filler is stretched, a large number of fine pores having the inorganic filler as a nucleus can be formed inside the base material. It is easy to whiten, opacify and lighten the base material. Moreover, since the resin component in the base material is replaced with pores having a carbon dioxide gas emission coefficient of 0, the amount of resin in the base material can be further reduced, and the amount of carbon dioxide gas emitted can be effectively reduced. Therefore, it is possible to reduce the environmental load.

The content of the inorganic filler is more than 45% by mass, preferably 50% by mass or more, more preferably 55% by mass or more, and still more preferably, from the viewpoint of reduction of environmental load and adhesion between the base layer and the resin coating. It is 60% by mass or more. From the viewpoint of moldability, the content of the inorganic filler is 80% by mass or less, preferably 75% by mass or less, and more preferably 70% by mass or less.

Examples of inorganic fillers include heavy calcium carbonate, light calcium carbonate, calcined clay, talc, diatomaceous earth, titanium oxide, zinc oxide, barium sulfate, silicon oxide, magnesium oxide, or fatty acids, polymeric surfactants, or antistatic fillers. Examples include inorganic particles surface-treated with an agent or the like. Among them, heavy calcium carbonate, light calcium carbonate, calcined clay or talc is preferable because of good pore moldability and low cost. From the viewpoint of improving whiteness or opacity, titanium oxide, zinc oxide or barium sulfate is preferred.

The base material may use an organic filler together with the above inorganic filler. The content of the organic filler in the substrate can be about 10% by mass or less, or 5% by mass or less.
Although the organic filler is not particularly limited, organic particles that are incompatible with the thermoplastic resin, have a higher melting point or glass transition temperature than the thermoplastic resin, and are finely dispersed under the melt-kneading conditions of the thermoplastic resin are preferred. For example, when the thermoplastic resin is a polyolefin resin, the organic filler includes polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polystyrene, polyamide, polycarbonate, polyethylene sulfide, polyphenylene sulfide, polyimide, polyether ketone, polyether ether. Examples include organic particles such as ketone, polymethyl methacrylate, poly-4-methyl-1-pentene, homopolymers of cyclic olefins, and copolymers of cyclic olefins and ethylene. Also, a fine powder of a thermosetting resin such as a melamine resin may be used, and it is also preferable to crosslink the thermoplastic resin to make it insoluble.
The melting point (°C) and glass transition temperature (°C) of the resin can be measured by differential scanning calorimetry (DSC).

One of the inorganic fillers and organic fillers may be selected from the above and used alone, or two or more thereof may be used in combination. When two or more types are combined, a combination of an inorganic filler and an organic filler may be used.

The average particle size of the inorganic filler and the organic filler is preferably large from the viewpoint of ease of mixing with the thermoplastic resin. In addition, the average particle size of the inorganic filler and the organic filler causes troubles such as sheet breakage during stretching or a decrease in the strength of the base material when voids are generated inside by stretching to improve opacity or printability. Smaller is preferable from the viewpoint of making it difficult to move. Specifically, the average particle size of the inorganic filler and the organic filler is preferably 0.01 µm or more, more preferably 0.1 µm or more, and still more preferably 0.5 µm or more. Also, the average particle size of the inorganic filler and the organic filler is preferably 30 μm or less, more preferably 20 μm or less, and even more preferably 15 μm or less.

The average particle size of the inorganic filler and the organic filler is obtained by observing the cut surface of the base material with an electron microscope and measuring the maximum size of at least 10 particles. It can be obtained as an average dispersed particle size when dispersed.

<<<Other Ingredients>>>
In the present invention, the substrate may optionally contain known additives as required. Additives include antioxidants, light stabilizers, ultraviolet absorbers, crystal nucleating agents, plasticizers, dispersants for fillers, slip agents such as fatty acid amides, antiblocking agents, dyes, pigments, mold release agents, or flame retardants. Known auxiliaries such as repellents can be used. In particular, when the recording paper is required to be durable, such as poster paper, which is used outdoors, it is preferable to contain an antioxidant or a light stabilizer.

Examples of antioxidants include sterically hindered phenol antioxidants, phosphorus antioxidants, amine antioxidants, and the like.
Examples of light stabilizers include sterically hindered amine light stabilizers, benzotriazole light stabilizers, benzophenone light stabilizers, and the like.
The content of the antioxidant and light stabilizer is preferably in the range of 0.001 to 1% by mass based on the mass of the substrate. Moreover, the content may be adjusted within a range that does not hinder the adhesion between the base material and the underlayer described later.

When a polyolefin resin is used as the thermoplastic resin, the transparency of the substrate can be enhanced by containing a crystal nucleating agent.
Examples of crystal nucleating agents include sorbitol-based nucleating agents, phosphate ester metal salt-based nucleating agents, amide-based nucleating agents, aromatic metal salt nucleating agents, and talc.
The content of the crystal nucleating agent is preferably 0.01% by mass or more, more preferably 0.05% by mass or more, and even more preferably 0.1% by mass or more, relative to the mass of the substrate. The content of the crystal nucleating agent is preferably 1% by mass or less, more preferably 0.5% by mass or less, and even more preferably 0.3% by mass or less.

When a polyester resin is used as the thermoplastic resin, it can be plasticized using a plasticizer. Examples of plasticizers include carboxylic acid esters such as phthalates and adipates; triacetin and the like.

The substrate may have a single layer structure or a multilayer structure. For example, the substrate may have a three-layer structure of first surface layer/core layer/second surface layer, and the core layer may impart suitable rigidity, opacity, or lightness to the recording paper. At this time, the types of components constituting the first surface layer and the second surface layer, the proportions of the components, and the thickness of the layers may be the same or different. In addition, by appropriately designing the composition, thickness, etc. of the first surface layer and the second surface layer, it is possible not only to suppress the curling of the base material, but also to control the curling when used as recording paper within a specific range. becomes possible. In addition, by providing a solid print layer or a pigment-containing layer as a concealing layer inside the first surface layer or the second surface layer, when viewed from one side, the printing on the other side does not show through, and double-sided printing is possible. It is also possible to improve the visibility at the time of printing, and it is possible to obtain recording paper suitable for poster paper and the like.
In addition, the substrate may have a two-layer structure, for example, a core layer and a surface layer (either the first surface layer on the side of the printed surface or the second surface layer on the side opposite to the printed surface). A layered substrate may also be used.

The thickness of the base material is preferably 30 μm or more, more preferably 50 μm or more, because mechanical strength sufficient for use as large-sized poster paper for outdoor display can be easily obtained. In addition, the thickness of the substrate is preferably 500 μm or less, more preferably 300 μm or less, because the weight of the recording paper is reduced and the handling property is easily improved.

<<<Porosity>>>
When the substrate has pores inside, the porosity, which indicates the ratio of pores in the substrate, is preferably 10% or more, and preferably 12% or more, from the viewpoint of opacification or reduction of environmental load. It is more preferably 15% or more, and particularly preferably 20% or more. From the viewpoint of maintaining mechanical strength, the porosity is preferably 45% or less, more preferably 44% or less, further preferably 42% or less, and 40% or less. is particularly preferred.

The porosity can be determined from the area ratio occupied by pores in a certain region of the cross section of the substrate observed with an electron microscope. Specifically, an arbitrary part of the substrate is cut, embedded in epoxy resin and solidified, then cut perpendicular to the surface direction of the substrate using a microtome, and the cut surface becomes the observation surface. Attach it to the observation sample table as shown. Gold or gold-palladium is vapor-deposited on the observation surface, and the pores are observed at an arbitrary magnification that is easy to observe with an electron microscope (for example, magnification of 500 to 3000 times), and the observed area is captured as image data. . Image processing is performed on the obtained image data by an image analysis device, and the area ratio (%) of the void portion can be obtained and used as the porosity (%). In this case, the porosity can be obtained by averaging the measured values obtained by observation at arbitrary 10 or more points.

<<Underlayer>>
In the present invention, the underlayer is made of a thermoplastic resin composition.
The indentation elastic modulus of the underlayer is 50 to 1200 MPa. As will be described later, the indentation modulus is determined by measuring the surface of the underlayer (the surface on which the resin coating is to be applied) by a nanoindentation test. When the indentation modulus is 50 MPa or more, blocking caused by an increase in adhesive strength over time or after storage under heat can be effectively suppressed. On the other hand, if the indentation elastic modulus is 1200 MPa or less, it is possible to effectively prevent deterioration of ink adhesion after printing.

From the above viewpoint, the indentation elastic modulus is preferably 70 MPa or more, more preferably 100 MPa or more, but is preferably 1,000 MPa or less, more preferably 900 MPa or less. Methods for controlling the indentation modulus within a preferred range include, for example, methods for controlling the type, content, viscoelasticity, or thickness of the material of the underlying layer. For example, the indentation modulus can be adjusted to be low by using various additives such as tackifiers and waxes described below, or by using olefinic resins with low surface free energy. In addition, the indentation elastic modulus can be adjusted to be high by increasing the thickness.

The thermoplastic resin that constitutes the base layer is not particularly limited as long as it does not impair the effects of the present invention, and the same thermoplastic resin as that for the substrate can be used.

Among the thermoplastic resins mentioned as the material for the base material, polyolefin resins or functional group-containing olefin resins are preferred, and polyolefin resins are more preferred, from the viewpoint of excellent film workability. Among polyolefin-based resins, polyethylene-based resins or polypropylene-based resins are preferable from the viewpoint of chemical resistance, workability, and low cost.

Examples of polyolefin-based resins include polyethylene-based resins (low-density polyethylene, medium-density polyethylene, high-density polyethylene, linear low-density polyethylene, low-crystalline or amorphous ethylene/α-olefin copolymer, ethylene-cyclic olefin copolymer, etc.), polypropylene resin (crystalline polypropylene, low-crystalline polypropylene, amorphous polypropylene, propylene/ethylene copolymer (random copolymer or block copolymer, etc.), propylene/α-olefin copolymer polymers, propylene/ethylene/α-olefin copolymers, etc.), polybutene, 4-methyl-1-pentene (co)polymers (poly(4-methyl-1-pentene), 4-methyl-1-pentene, α-olefin copolymers, etc.). The α-olefin is not particularly limited as long as it can be copolymerized with ethylene, propylene, 4-methyl-1-pentene. Examples include ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-heptene, 1-octene and the like can be mentioned.
Functional group-containing olefin resins include, for example, ethylene-ethyl (meth)acrylate copolymer, ethylene-methyl (meth)acrylate copolymer, ethylene-n-butyl (meth)acrylate copolymer, ethylene- vinyl acetate copolymer, maleic acid-modified polyethylene, maleic acid-modified polypropylene, and the like.
These may be used alone or in combination.

The base layer may contain other components such as waxes, tackifiers, lubricants, and other additives in addition to those mentioned above, as long as the objects of the present invention are not impaired. Among them, it is preferable to contain a tackifier.

Examples of tackifiers include aliphatic copolymers, aromatic copolymers, petroleum resins such as aliphatic/aromatic copolymers and alicyclic copolymers, terpene resins, terpene Phenol-based resins, rosin-based resins, alkylphenol-based resins, xylene-based resins, or hydrogenated products thereof can be used. The content of the tackifier in the underlayer is preferably 0.1% by mass or more, preferably 0.2% by mass or more, but is preferably 10% by mass or less, and more preferably 8% by mass or less.

Examples of waxes that can be used include paraffin waxes, olefin waxes, and modified waxes thereof. For example, in the case of olefin wax, polyethylene wax, polypropylene wax, polybutene wax or modified waxes thereof can be used. The wax content in the underlayer is preferably 10% by mass or less. If it is 10% by mass or less, it is easy to suppress a decrease in adhesiveness.

Examples of lubricants include fatty acids, fatty acid amides, and fatty acid metals having at least one alkyl or alkenyl group having 4 to 60 carbon atoms, particularly a linear alkyl or alkenyl group having 4 to 30 carbon atoms in the molecule. Salts can be used, and more specific examples include fatty acids such as lauric acid, palmitic acid, stearic acid, behenic acid, oleic acid, and erucic acid, and metal salts or amide compounds of these fatty acids. The content of the lubricant in the underlayer is preferably 2% by mass or less, more preferably 1% by mass or less, from the viewpoint of reducing bleeding out and the like.

Other additives include, for example, antioxidants, weathering agents, antistatic agents, and the like. These additives may be used alone or in combination.

The thickness of the underlayer is preferably 1 μm or more, more preferably 2 μm or more, from the viewpoint of enhancing the adhesion between the laminated resin film and the resin coating. From the viewpoint of imparting appropriate roughness to the surface of the underlayer, the thickness of the underlayer is preferably 50 μm or less, more preferably 30 μm or less, and even more preferably 20 μm or less. The thickness of the recording paper is preferably 500 μm or less from the viewpoint of lightening the weight of the recording paper itself and improving the handleability. Therefore, from the viewpoint of adjusting the thickness within that range, the thickness of the underlayer is 200 μm or less. is preferred.

Underlayers having an indentation modulus of 50 to 1200 MPa may be disposed on both sides of the substrate. For example, as will be described later, when resin coatings are arranged on both sides of the substrate, it is preferable to arrange the underlayers on both sides of the substrate. The proportions of the components can be the same or different.

<<Method for producing laminated resin film>>
The base material or base layer in the laminated resin film (hereinafter, the "base material or base layer in the laminated resin film" is also referred to as "each layer in the laminated resin film") is usually included in the above-described thermoplastic resin and layer. It can be obtained by molding after mixing other ingredients. The molding method is not particularly limited, and various known molding methods can be used alone or in combination.

Each layer in the laminated resin film is formed by, for example, cast molding, calendar molding, roll molding, inflation molding, etc., in which molten resin is extruded into a sheet by a single-layer or multi-layer T die, I die, etc. connected to a screw type extruder. , can be formed into a film. Each layer in the laminated resin film may be formed by casting or calendering a mixture of a thermoplastic resin and an organic solvent or oil and then removing the solvent or oil.

Each layer in the laminated resin film may be formed separately, and a laminated body of the laminated resin film may be formed by laminating the formed layers. Alternatively, the laminate may be obtained by molding together with other layers. For example, by using a molding method such as co-extrusion, it is possible to obtain a laminate in which the substrate and the underlayer are collectively laminated together.
Further, as described above, the base material may have a single-layer structure or a multi-layer structure. In this case, for example, when the base material has a multi-layered structure consisting of the first surface layer/core layer/second surface layer, these layers are molded separately and then laminated by laminating the molded layers. A substrate having a multilayer structure may be obtained, or a substrate having a multilayer structure may be obtained by molding together with other layers.

Examples of molding methods for laminating a plurality of layers together in a laminated resin film include a multi-layer die method using a feed block and a multi-manifold, an extrusion lamination method using a plurality of dies, and the like. A combination of methods is also possible.

Each layer in the laminated resin film may be a non-stretched film or a stretched film.
Stretching methods include, for example, a longitudinal stretching method using a difference in circumferential speed between rolls, a transverse stretching method using a tenter oven, a sequential biaxial stretching method combining these methods, a rolling method, and a simultaneous two-stretching method using a combination of a tenter oven and a pantograph. Examples include an axial stretching method and a simultaneous biaxial stretching method using a combination of a tenter oven and a linear motor. A simultaneous biaxial stretching (inflation molding) method can also be used, in which a circular die connected to a screw extruder is used to extrude a molten resin into a tubular shape, and then air is blown into the tubular shape.

At least one layer of the substrate and the underlayer in the laminated resin film is preferably stretched from the viewpoint of imparting appropriate stiffness to the recording paper and improving workability when used as a label. From the viewpoint of reducing the environmental load by the porosity, it is preferable that the substrate is stretched. The substrate is preferably a porous stretched layer because pores are formed in the substrate by stretching the substrate containing the inorganic filler.
Moreover, when the substrate has a multilayer structure, at least one layer thereof is preferably stretched.
When stretching a plurality of layers, each layer may be stretched individually before lamination, or may be stretched collectively after lamination. Further, the stretched layer may be stretched again after lamination.

When the thermoplastic resin used in each layer in the laminated resin film is an amorphous resin, the stretching temperature when stretching is preferably in the range of the glass transition temperature of the thermoplastic resin or higher. Also, when the thermoplastic resin is a crystalline resin, the stretching temperature should be above the glass transition point of the non-crystalline portion of the thermoplastic resin and below the melting point of the crystalline portion of the thermoplastic resin. is preferred, and specifically, a temperature lower than the melting point of the thermoplastic resin by 2 to 60°C is preferred.

The stretching speed for molding each layer in the laminated resin film is not particularly limited, but from the viewpoint of stable stretching molding, it is preferably within the range of 20 to 350 m/min.
In addition, the draw ratio for molding each layer in the laminated resin film can also be appropriately determined in consideration of the properties of the thermoplastic resin to be used. For example, when a thermoplastic resin film containing a propylene homopolymer or a copolymer thereof is stretched in one direction, the draw ratio is usually about 1.2 times or more, preferably about 2 times or more. , is usually 12 times or less, preferably 10 times or less. On the other hand, the draw ratio in biaxial stretching is usually 1.5 times or more, preferably 3 times or more, and usually 60 times or less, preferably 50 times or less, in terms of area draw ratio. .

Further, when a thermoplastic resin film containing a polyester resin is stretched in one direction, the stretch ratio is usually 1.2 times or more, preferably 2 times or more, and usually 10 times or less. It is preferably 5 times or less. The draw ratio in biaxial stretching is usually 1.5 times or more, preferably 3 times or more, and usually 20 times or less, preferably 12 times or less, in terms of area draw ratio.
Especially, if the stretch ratio of the base material containing the inorganic filler is within the above range, the target porosity is easily obtained, the opacity is easily improved, and the environmental load is easily reduced, which is preferable. In addition, there is a tendency that the base material is less likely to be broken, and that stable stretch molding can be performed.

<<Surface treatment>>
In the laminated resin film, the underlayer is preferably subjected to a surface treatment so as to activate the surface from the viewpoint of enhancing adhesion to the resin film.
Examples of surface treatment include corona discharge treatment, flame treatment, plasma treatment, glow discharge treatment, ozone treatment, and the like, and these treatments can be combined. Among them, corona discharge treatment or flame treatment is preferable, and corona treatment is more preferable.

The amount of discharge when performing corona discharge treatment is preferably 600 J/m ² (10 W·min/m ² ) or more, more preferably 1,200 J/m ² (20 W·min/m ² ) or more. . The discharge amount is preferably 12,000 J/m ² (200 W·min/m ² ) or less, more preferably 10,800 J/m ² (180 W·min/m ² ) or less. The amount of discharge when flame treatment is performed is preferably 8,000 J/m ² or more, more preferably 20,000 J/m ² or more. Also, the discharge amount is preferably 200,000 J/m ² or less, more preferably 100,000 J/m ² or less.
In particular, the elemental composition ratio (O/C) of oxygen to carbon on the surface of the underlayer after surface treatment is preferably 0.01 to 0.5. If the value of the elemental composition ratio (O/C) is within the above range, the adhesion to the resin coating is further improved.

The elemental composition ratio (O / C) is obtained by XPS (X-ray electron optical spectroscopy) measurement on the surface after surface treatment, multiplying the relative sensitivity of each peak to the peak intensity area of each of O1s and C1s It is the abundance ratio (O / C) of oxygen and carbon obtained from the ratio of the values (for example, Yoshito Irakawa, "Fundamentals and Applications of Polymer Surfaces (Part 1)", published by Kagaku Dojin, 1986, Chapter 4 reference). The value of the elemental composition ratio (O/C) can be adjusted within the above range depending on the surface treatment conditions. For example, the surface treatment conditions are 60 W·min/m ² (3,600 J/m ² ) to 400 W·min/m ² (24,000 J/m ² ), so that the elemental composition ratio (O/C) is It can be adjusted within the above range.

<Resin coating>
The resin film contains a resin that is a reaction product of a cationic water-soluble polymer and a silane coupling agent, and optionally an inorganic filler, and does not contain thermoplastic resin particles. The resin film in the present invention is usually a film on which characters, images, etc., can be recorded by printing, writing instruments, or the like.

<<Method for producing resin coating>>
The resin coating in the present invention contains a cationic water-soluble polymer and a silane coupling agent, optionally contains an inorganic filler, and does not contain thermoplastic resin particles, on the surface of the laminated resin film on the underlayer side. It can be formed by applying an aqueous solution (hereinafter sometimes referred to as a "coating liquid for forming a resin film") and then drying it. Here, the reaction rate between the cationic water-soluble polymer and the silane coupling agent may not be 100%. That is, the resin coating may contain an unreacted cationic water-soluble polymer and a silane coupling agent in addition to the resin that is the reactant (reaction product). Moreover, the coating liquid for forming a resin film can be obtained by mixing the cationic water-soluble polymer, the silane coupling agent and the aqueous solvent, and then stirring the mixture. The coating liquid for forming a resin film may be obtained by mixing an aqueous solution of a cationic water-soluble polymer and an aqueous solution of a silane coupling agent.
The cationic water-soluble polymer (unreacted component), the silane coupling agent (unreacted component), and the reaction product between the cationic water-soluble polymer and the silane coupling agent in the resin film were analyzed by time-of-flight secondary ion mass spectrometry. (TOF-SIMS: Time-of-Flight Secondary Ion Mass Spectrometry).

The resin film containing the resin that is the reaction product contains olefin copolymer particles derived from the emulsion, compared with a resin film formed by applying a coating liquid containing an olefin copolymer emulsion. There are few unevenness on the surface because there is no surface. Therefore, it is possible to obtain a recording paper having high glossiness and transparency and an excellent appearance. Since there is little peeling of the resin coating, fluffing is less likely to occur. In addition, this resin film has sufficient adhesion to a homopolymer thermoplastic resin such as homopolypropylene, which generally has low adhesion to other resins. Adhesion to the object can be enhanced regardless of the type of thermoplastic resin used. That is, since the resin coating has high adhesion to the base material, the coating may be directly provided on the base material, but the adhesion to the base material is further improved by interposing the base layer. In the recording paper of the invention, the resin coating is provided on the underlayer. In addition, the resin film is suitable not only for inks used in general printing methods such as offset printing methods and UV flexographic printing methods using oil-based inks and UV inks, but also for UV inkjet printing methods and dry electrophotographic printing methods. Furthermore, even when a liquid toner used in wet electrophotographic printing is used, sufficiently high adhesion, particularly water-resistant adhesion, can be obtained. Therefore, it is possible to provide a recording paper having printability for various printing methods including the wet electrophotographic printing method, and by using the recording paper, the printed matter has high water resistance and little dropout of ink or toner. can provide

<<Cationic water-soluble polymer>>
In the resin coating, the cationic water-soluble polymer is contained as a resin that is a reactant with the silane coupling agent. However, as described above, the resin coating may contain unreacted cationic water-soluble polymer.
Due to the polar groups possessed by the cationic water-soluble polymer, the resin film is chemically adhered to the ink or toner (specifically, adhesion by ionic bonding) and dispersedly adhered (specifically, by Van der Waals force). ), and it is presumed that the transferability and adhesion of the ink or toner to the resin film are improved.

The water-solubility of the cationic water-soluble polymer may be such that the water-soluble medium containing the cationic water-soluble polymer is in a solution state when the resin film-forming coating solution is prepared.

Examples of cationic water-soluble polymers that can be used include (meth)acrylic polymers or ethyleneimine polymers having an amino group or ammonium salt structure, water-soluble polymers having a phosphonium salt structure, polyvinylpyrrolidone, polyvinyl alcohol, and the like. Examples include vinyl-based polymers obtained by cationizing polymers by modification, and one of these can be used alone or two or more of them can be used in combination. Among them, a (meth)acrylic polymer or an ethyleneimine polymer having an amino group or an ammonium salt structure is preferable from the viewpoint of transferability and adhesion of the ink or toner to the resin film.

A (meth)acrylic polymer or ethyleneimine polymer having an amino group or an ammonium salt structure has a primary to tertiary amino group or a primary to tertiary ammonium salt from the viewpoint of safety. It preferably has a structure, more preferably has a secondary to tertiary amino group or a secondary to tertiary ammonium salt structure, a tertiary amino group or a tertiary ammonium salt structure It is further preferred to have In addition, from the viewpoint that a resin having a high degree of cross-linking can be obtained by reaction with a silane coupling agent, and high adhesion between an ink or toner and a resin film can be obtained, a primary to tertiary amino group or a tertiary Primary to tertiary ammonium salt structures are preferred, primary to secondary amino groups or primary to secondary ammonium salt structures are more preferred, primary amino groups or primary Ammonium salt structures are more preferred.

Among them, ethyleneimine-based polymers have a high affinity with inks or toners used in various printing methods, particularly with ultraviolet curable inks used in flexographic printing methods, and therefore the adhesion between the resin film and the ink is improved. improved and preferred.
Examples of ethyleneimine-based polymers include polyethyleneimine, poly(ethyleneimine-urea), ethyleneimine adducts of polyamine polyamides, alkyl modified products thereof, cycloalkyl modified products, aryl modified products, allyl modified products, aralkyl modified products, Examples include benzyl modified products, cyclopentyl modified products, cycloaliphatic hydrocarbon modified products, glycidol modified products, and hydroxides thereof. Examples of modifying agents for obtaining modified compounds include methyl chloride, methyl bromide, n-butyl chloride, lauryl chloride, stearyl iodide, oleyl chloride, cyclohexyl chloride, benzyl chloride, allyl chloride, and cyclopentyl chloride.

〔上記式（Ｉ）中、Ｒ^１とＲ^２はそれぞれ独立して水素原子；炭素数１～１２の直鎖又は分岐状のアルキル基；炭素数６～１２の脂環式構造を有するアルキル基又はアリール基を表す。Ｒ^３は水素原子；ヒドロキシ基を含んでいてもよい炭素数１～１８の範囲のアルキル基又はアリル基；ヒドロキシ基を含んでいてもよい炭素数６～１２の脂環式構造を有するアルキル基又はアリール基を表す。ｍは２～６の整数を表し、ｎは２０～３０００の整数を表す。〕 Among them, an ethyleneimine-based polymer represented by the following general formula (I) is preferable from the viewpoint of improving transferability and adhesiveness of ink or toner used for printing, particularly ultraviolet curable ink.

[In the above formula (I), R ¹ and R ² are each independently a hydrogen atom; a linear or branched alkyl group having 1 to 12 carbon atoms; an alkyl group having an alicyclic structure having 6 to 12 carbon atoms; or represents an aryl group. R ³ is a hydrogen atom; an alkyl group or allyl group having 1 to 18 carbon atoms and optionally containing a hydroxy group; an alkyl group having an alicyclic structure having 6 to 12 carbon atoms and optionally containing a hydroxy group. or represents an aryl group. m represents an integer of 2-6, and n represents an integer of 20-3000. ]

Commercially available products can also be used as the (meth)acrylic polymer or ethyleneimine polymer having an amino group or an ammonium salt structure.
Examples of commercially available (meth)acrylic polymers having an amino group or an ammonium salt structure include Polyment (manufactured by Nippon Shokubai Co., Ltd.).
Commercially available ethyleneimine polymers include Epomin (manufactured by Nippon Shokubai Co., Ltd.) and Polymin SK (manufactured by BASF).

The weight-average molecular weight of the (meth)acrylic polymer or ethyleneimine polymer having an amino group or an ammonium salt structure is 10,000 or more from the viewpoint of improving adhesion to substrates and adhesion to inks and the like. It is preferably 20,000 or more, more preferably 20,000 or more. On the other hand, the weight average molecular weight is preferably 1,000,000 or less, more preferably 500,000 or less.
In the present invention, the weight average molecular weight and number average molecular weight of the resin can be obtained by converting values measured by GPC (Gel Permeation Chromatography) into polystyrene.

The resin film-forming coating liquid may contain a polymer other than the cationic water-soluble polymer within a range that does not significantly impair the expression of the excellent effect of the resin film.

<<Silane coupling agent>>
In the resin coating, the silane coupling agent is contained as a resin that is a reactant with the cationic water-soluble polymer. However, as described above, the resin coating may contain an unreacted silane coupling agent.

It is presumed that the silane coupling agent contributes to the expression of the function of increasing the adhesion between the laminated resin film and the resin coating.
Specifically, the silane coupling agent has a functional group that is highly reactive with organic materials, and this functional group causes a cross-linking reaction between the thermoplastic resin of the underlayer and the cationic water-soluble polymer to form a laminated resin film. It is presumed that this increases the adhesion of the resin film and prevents moisture from entering between the laminated resin film and the resin coating. It is presumed that this suppresses peeling of the resin coating, and consequently, peeling of the ink or toner from the printed matter, thereby enhancing the abrasion resistance. In addition, the silane coupling agent causes a cross-linking reaction between the cationic water-soluble polymers to form a network structure, and it is presumed that this network structure enhances the transferability and adhesiveness of the ink or toner. Furthermore, the silane coupling agent cross-links with the cationic water-soluble polymer to increase the molecular weight of the hydrophilic component (polar resin component) of the cationic water-soluble polymer, presumably to improve water resistance. be done.

As the silane coupling agent, a silane coupling agent having various functional groups such as a group that reacts with the cationic water-soluble polymer, for example, a silanol group can be used. A group that reacts with a cationic water-soluble polymer refers to a group that forms a bond by reacting with an atom or atomic group possessed by the cationic water-soluble polymer. Bonds formed by the reaction may be covalent bonds, ionic bonds, hydrogen bonds, or the like, and are not particularly limited.

Specifically, in the molecule, together with an alkoxysilyl group or a silanol group obtained by hydrolysis of an alkoxysilyl group, an epoxy group, a vinyl group, a (meth)acrylic group, an amino group, a ureido group, a mercapto group, an isocyanate group, etc. A silane coupling agent having at least one functional group other than a silanol group can be used.

The silane coupling agent is a (meth)acrylic polymer having an amino group or ammonium salt structure in which the silanol group undergoes a condensation reaction with the thermoplastic resin of the underlying layer, while the functional group other than the silanol group is contained in the resin film. ) Condensation reaction with acrylic acid residues, amino groups in the ethyleneimine polymer, etc., is presumed to cause a cross-linking reaction.
Alternatively, the silane coupling agent has a silanol group or (meth)acrylic acid residue in the (meth)acrylic polymer having an amino group or ammonium salt structure, while condensing with the amino group in the ethyleneimine polymer, silanol It is presumed that the cross-linking reaction is performed by the functional groups other than the groups being linked with the thermoplastic resin of the underlayer with high affinity.

The content of alkoxysilyl groups or hydrolyzed silanol groups in the silane coupling agent is 25 from the viewpoint of strong adhesion between the laminated resin film and the resin coating, and strong adhesion between the resin coating and the ink or toner. % or more, more preferably 50% or more, and preferably 75% or less. In addition, the content of reactive functional groups other than alkoxysilyl groups or silanol groups hydrolyzed by alkoxysilyl groups in the silane coupling agent is preferably 25% or more, preferably 75% or less, and 50% or less. is more preferable.

Specific examples of usable silane coupling agents include epoxy silane coupling agents, vinyl silane coupling agents, (meth)acrylic silane coupling agents, amino silane coupling agents, ureido silane coupling agents, A mercapto-based silane coupling agent, an isocyanate-based silane coupling agent, and the like are included.

Examples of epoxy-based silane coupling agents include 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, and 3-glycidoxypropyltriethoxysilane. , 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane and the like. Among them, 3-glycidoxypropyltrimethoxysilane is preferable from the viewpoint of adhesion to ink or toner.
Vinyl-based silane coupling agents include, for example, vinyltrimethoxysilane and vinyltriethoxysilane.
(Meth)acrylic silane coupling agents include, for example, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane and the like.

Examples of amino-based silane coupling agents include N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane, N-2-(aminoethyl)-3-aminopropyltrimethoxysilane, and 3-aminopropyltrimethoxysilane. Silane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N-(1,3-dimethyl-butylidene)propylamine, N-phenyl-3-aminopropyltrimethoxysilane, N-(vinylbenzyl)-2 -aminoethyl-3-aminopropyltrimethoxysilane and the like.

Ureido-based silane coupling agents include, for example, 3-ureidopropyltriethoxysilane.
Mercapto-based silane coupling agents include, for example, 3-mercaptopropylmethyldimethoxysilane and 3-mercaptopropyltrimethoxysilane.
Isocyanate-based silane coupling agents include, for example, 3-isocyanatopropyltriethoxysilane.
These silane coupling agents can be used alone or in combination of two or more.

Commercially available silane coupling agents include KBM-303, KBM-402, KBM-403, KBE-402, KBE-403, KBM-1003, KBE-1003, KBM-502, and KBM manufactured by Shin-Etsu Chemical Co., Ltd. -503, KBE-502, KBE-503, KBM-5103, KBM-602, KBM-603, KBM-903, KBE-903, KBE-9103, KBM-573, KBM-575, KBE-585, KBM-802 , KBM-803, KBE-9007 (both trade names); Z-6043, Z-6040, Z-6519, Z-6300, Z-6030, Z-6011, Z-6094 manufactured by Dow Corning Toray Co., Ltd. , Z-6062 (both are trade names), etc. can be used.

Among these, epoxy-based silane coupling agents, amino-based silane coupling agents, mercapto-based silane coupling agents, and isocyanate-based silane coupling agents are preferable from the viewpoint of adhesion to ink or toner. agent or an amino-based silane coupling agent is more preferred, and an epoxy-based silane coupling agent is even more preferred.
From the viewpoint of ease of cross-linking reaction with primary to tertiary amino groups possessed by the cationic water-soluble polymer, an epoxy-based silane coupling agent, a ureido-based silane coupling agent or an isocyanate-based silane coupling agent is used. An epoxy-based silane coupling agent is preferred, and an epoxy-based silane coupling agent is more preferred.

From the viewpoint of applicability to laminated resin films, vinyl-based silane coupling agents or (meth)acrylic-based silane coupling agents are preferable when polyolefin-based resins are used as the thermoplastic resin of the underlayer.
In addition, when metal oxide particles such as inorganic fillers are present on the surface of the base material, amino-based silane coupling agents and ureido-based silane coupling agents are used from the viewpoint of strongly bonding with the particles and enhancing adhesion to the base material. or a mercapto-based silane coupling agent is preferably used.

The silane coupling agent is known to be able to control the hydrolysis rate depending on the type of alkoxysilyl group, and this property can be used to prevent deterioration of the resin film-forming coating solution due to self-condensation of the silane coupling agent. can be suppressed and stability over time can be enhanced. Epoxy-based silane coupling agents are preferred as silane coupling agents from the viewpoints of high solubility in water, easy preparation of a coating solution for forming a resin film, and high stability over time. 3-glycidoxypropyltrimethoxysilane is preferred.

In the coating liquid for forming a resin film, the alkoxysilane group in the silane coupling agent molecule is changed to a silanol group by hydrolysis, and the silanol group is on the underlayer, especially on the surface-treated underlayer. It is presumed that the adhesion between the base material or laminated resin film and the resin coating is improved by chemical bonding such as hydrogen bonding with functional groups such as hydroxy groups and carboxy groups. In addition, it is presumed that the condensation reaction between the silanol groups improves the cohesive force of the resin coating itself and also improves the physical strength of the resin coating itself.

From the viewpoint that the resin film has excellent adhesion to the ink or toner, it is preferable that the amount of the unreacted silane coupling agent contained in the resin film-forming coating liquid is not too large. By adjusting the amount of unreacted components to an appropriate level, the resin coating obtained from too much unreacted silane coupling agent becomes hard and cannot follow the bending of the recording paper, resulting in cracking and peeling of the ink or toner. can be reduced. Moreover, from the point of view of the excellent water resistance of the resin film, it is preferable that the amount of unreacted cationic water-soluble polymer is small. From these points of view, the amount of the silane coupling agent in the resin film-forming coating solution is 15 parts by mass or more, preferably 17 parts by mass or more, relative to 100 parts by mass of the cationic water-soluble polymer. , 60 parts by mass or less, preferably 55 parts by mass or less, more preferably 50 parts by mass or less, even more preferably 35 parts by mass or less, and particularly preferably 30 parts by mass or less , 25 parts by mass or less. That is, the content of the silane coupling agent component (the total amount of unreacted and reacted portions; the same shall apply hereinafter) in the resin coating is the same as the content of the cationic water-soluble polymer component (the total amount of unreacted and reacted portions) in the resin coating. The same applies hereinafter.) It is 15 parts by mass or more, preferably 17 parts by mass or more, and 60 parts by mass or less, preferably 55 parts by mass or less, and 50 parts by mass or less per 100 parts by mass. is more preferably 35 parts by mass or less, particularly preferably 30 parts by mass or less, and most preferably 25 parts by mass or less.

Within this range, for example, when the recording paper according to the present invention is used in a wet electrophotographic printing method using a liquid toner, the adhesion to the toner is sufficient, the water resistance is high, and the toner does not come off. It can be a hard printed matter.

<<Inorganic filler>>
The content of the inorganic filler in the resin film-forming coating liquid is 9 parts by mass or less with respect to 100 parts by mass of the cationic water-soluble polymer. That is, it does not contain an inorganic filler, or if it contains an inorganic filler, the content is 9 parts by mass or less. If the content of the inorganic filler is 9 parts by mass or less with respect to 100 parts by mass of the cationic water-soluble polymer, it is possible to effectively prevent white spots in the printed portion due to unevenness of the resin film caused by the inorganic filler, and a high ink transfer rate. can be realized. In the present invention, since the base material contains a large amount of inorganic filler, the surface of the base layer can be given an appropriate roughness, but the content of the inorganic filler in the resin coating is within the above range , the roughness of the underlayer is less likely to appear as the roughness of the surface of the resin coating. In addition, it is possible to effectively prevent contamination of the recording paper due to falling-off of the inorganic filler, and to better reflect the texture (paper quality) of the laminated resin film. From such a viewpoint, the content of the inorganic filler is preferably 5 parts by mass or less, more preferably 3 parts by mass or less, even more preferably 0.1 parts by mass or less, and particularly preferably no inorganic filler.
That is, the content of the inorganic filler in the resin film in the present invention is 9 parts by mass or less, preferably 5 parts by mass or less, more preferably 3 parts by mass or less per 100 parts by mass of the cationic water-soluble polymer component. more preferably 0.1 parts by mass or less, and particularly preferably 0 parts by mass (not included).

On the other hand, from the viewpoint of blocking prevention, it is preferable to contain a small amount of inorganic filler in the resin film. It is preferably 0.1 parts by mass or more, more preferably 0.2 parts by mass or more, and even more preferably 0.3 parts by mass or more. That is, the content of the inorganic filler in the resin film in the present invention is preferably 0.1 parts by mass or more, more preferably 0.2 parts by mass or more, relative to 100 parts by mass of the cationic water-soluble polymer component. , more preferably 0.3 parts by mass or more.

The resin film-forming coating liquid may contain other auxiliary components such as an antistatic agent, a cross-linking accelerator, an antiblocking agent, a pH adjuster, and an antifoaming agent, if necessary. That is, the resin coating may contain other auxiliary components such as an antistatic agent, a cross-linking accelerator, an antiblocking agent, a pH adjuster, and an antifoaming agent, if necessary.

<<Antistatic agent>>
The resin film in the present invention preferably contains an antistatic agent from the viewpoint of preventing adhesion of dust due to charging and transportation failure during printing, and improving handling properties as recording paper.
Among the antistatic agents, polymer type antistatic agents are preferable from the viewpoint of reducing surface contamination due to bleeding out.
The polymer-type antistatic agent is not particularly limited, and cationic, anionic, amphoteric or nonionic antistatic agents can be used, and these can be used alone or in combination of two or more. .

Examples of cationic antistatic agents include antistatic agents having an ammonium salt structure, a phosphonium salt structure, or the like. Examples of anionic antistatic agents include antistatic agents having a structure of an alkali metal salt (lithium salt, sodium salt, potassium salt, etc.) of sulfonic acid, phosphoric acid, carboxylic acid, or the like. The anionic antistatic agent may be an antistatic agent having an alkali metal salt structure such as acrylic acid, methacrylic acid, (anhydrous) maleic acid, etc. in the molecular structure.

Examples of amphoteric antistatic agents include antistatic agents containing structures of both a cationic antistatic agent and an anionic antistatic agent in the same molecule. Amphoteric antistatic agents include betaine antistatic agents. Examples of nonionic antistatic agents include ethylene oxide polymers having an alkylene oxide structure and polymers having an ethylene oxide polymerization component in the molecular chain. Other antistatic agents include polymeric antistatic agents having boron in the molecular structure.

Among them, the polymer-type antistatic agent is preferably a cationic antistatic agent, more preferably a nitrogen-containing polymer-type antistatic agent, more preferably an antistatic agent having an ammonium salt structure, a tertiary or quaternary ammonium salt. Structured acrylic resins are particularly preferred, and acrylic resins having a quaternary ammonium salt structure are most preferred.
Commercially available products such as Saftomer ST-1000, ST-1100 and ST-3200 (trade names) manufactured by Mitsubishi Chemical Corporation can be used as the polymer-type antistatic agent.
As the polymer-type antistatic agent, a compound that reacts with the silane coupling agent may be used, or a compound that does not react with the silane coupling agent may be used. However, a compound that does not react with the silane coupling agent is preferable from the viewpoint of facilitating the development of antistatic performance.

From the viewpoint of antistatic, the amount of the antistatic agent contained in the coating liquid for forming the resin film is preferably 0.01 parts by mass or more with respect to 100 parts by mass of the cationic water-soluble polymer, and 1 part by mass. It is more preferably 2 parts by mass or more, more preferably 2 parts by mass or more. Moreover, from the viewpoint of the water resistance of the resin film, the amount of the antistatic agent contained in the coating solution for forming the resin film is preferably 45 parts by mass or less with respect to 100 parts by mass of the cationic water-soluble polymer. , 40 parts by mass or less, more preferably 35 parts by mass or less.

<<crosslinking accelerator>>
Examples of cross-linking accelerators include phosphoric acid, sulfuric acid, citric acid, and succinic acid.

The thickness of the resin coating is preferably 0.01 to 5 μm. From the viewpoint of stably forming a uniform resin coating, the thickness of the resin coating is preferably 0.01 μm or more, more preferably 0.02 μm or more, and further preferably 0.03 μm or more. preferable. In addition, from the viewpoint of effectively suppressing the bleeding out of additives and low-molecular-weight compounds contained in the laminated resin film and having good ink transferability even after being stored in a hot and humid environment, the resin film is relatively thick. is preferred. Specifically, it is preferably 0.1 μm or more, more preferably 0.25 μm or more, and even more preferably 0.3 μm or more.

On the other hand, from the viewpoint of effectively preventing deterioration in adhesion to the laminated resin film due to cohesive failure of the resin coating, the thickness of the resin coating is preferably 5 μm or less, more preferably 3 μm or less, and more preferably 1.5 μm. More preferably: Moreover, from the viewpoint of better reflecting the texture (paper quality) of the laminated resin film, it is preferable that the resin coating is relatively thin. Specifically, it is preferably 1.0 μm or less, more preferably 0.8 μm or less, and even more preferably 0.5 μm or less.

<<Thermoplastic resin particles>>
The resin coating does not contain thermoplastic resin particles, as described above. The thermoplastic resin particles refer to particles derived from an emulsion of a thermoplastic resin such as an olefin copolymer dispersed in a dispersion medium in a coating liquid for forming a resin film.
By not containing thermoplastic resin particles, it is possible to avoid blocking caused by heat fusion of the thermoplastic resin and changes in the glossiness of the resin film surface before and after printing or molding. In addition, the uniformity of the surface of the resin film is improved, and a recording paper excellent in appearance such as gloss and transparency can be obtained. In addition, the adhesiveness to the toner, especially the liquid toner of the wet electrophotographic printing method using liquid toner is improved, and even when the thermoplastic resin used for the base layer of the laminated resin film contains homopolypropylene. , the adhesion to the laminated resin film is also improved.
The fact that the resin coating does not contain thermoplastic resin particles and the uniformity of the surface of the resin coating can be confirmed by observation with a scanning electron microscope or the like.

The olefinic copolymer emulsion is an emulsion obtained by dispersing or emulsifying fine particles of an olefinic copolymer in an aqueous dispersion medium, as disclosed in WO 2014/092142. Nonionic or cationic surfactants, nonionic or cationic water-soluble polymers, etc. may be used as dispersants in this emulsion.

Examples of the olefinic copolymer to be dispersed or emulsified in the emulsion include olefinic copolymers having good emulsifiability and containing a structural unit containing a carboxy group or a salt thereof as a copolymerization component. Representative examples of such copolymers include copolymers of olefinic monomers and unsaturated carboxylic acids or their anhydrides, and salts thereof. Specific examples include ethylene-(meth)acrylic acid copolymers, ethylene-(meth)acrylic acid ester copolymers, ethylene-(meth)acrylic acid copolymer alkali (earth) metal salts, ethylene-( meth)acrylate-maleic anhydride copolymer, (meth)acrylic acid grafted polyethylene, ethylene-vinyl acetate copolymer, maleic anhydride-grafted polyethylene, maleic anhydride-grafted ethylene-vinyl acetate copolymer, maleic anhydride Grafted (meth)acrylic acid ester-ethylene copolymer, maleic anhydride grafted polypropylene, maleic anhydride grafted ethylene-propylene copolymer, maleic anhydride grafted ethylene-propylene-butene copolymer, maleic anhydride grafted ethylene-butene copolymers, maleic anhydride-grafted propylene-butene copolymers, and the like.

The olefinic copolymer particles in the emulsion are usually particles having a volume average particle diameter of about 0.2 to 3 μm. The volume-average particle diameter is the volume-average particle diameter measured using a laser diffraction particle size distribution analyzer (manufactured by Shimadzu Corporation: SALD-2200).

As disclosed in WO 2014/092142, when thermoplastic resin particles other than olefin copolymer particles, such as acrylic copolymer particles or urethane copolymer particles, are contained in the resin coating, olefin Adhesion to toners, especially liquid toners for wet electrophotographic printing, becomes more insufficient than in the case of containing system copolymer particles.

Although the resin coating is arranged facing the base layer of the laminated resin film, the resin coating may be formed not only on one surface of the laminated resin film but also on both surfaces of the laminated resin film. For example, when underlayers are arranged on both sides of the substrate, a resin film may be formed on each underlayer. Alternatively, an underlayer may be provided on one surface of the substrate, and in addition to forming the resin coating on the underlayer, the resin coating may be further formed on the other surface of the substrate.

<How to use recording paper>
As described above, the resin coating in the recording paper of the present invention is a recordable film. Examples of recording methods include printing and recording with writing instruments.
The recording paper of the present invention can be printed by various methods including offset printing, letterpress printing, gravure printing, flexographic printing, and screen printing. Due to its excellent weather resistance and durability, it is suitable as printing paper for posters used indoors and outdoors, stickers used indoors and outdoors, labels for frozen food containers, industrial product names (labels that describe usage and precautions), etc. used for
The recording paper of the present invention is particularly excellent in toner adhesion of printed matter obtained by a wet electrophotographic printing method using liquid toner, and is suitable for applications in which small-lot printing and variable information printing are performed. . In addition, the recording paper of the present invention is excellent not only in the printed material itself but also in the water resistance of the laminated printed material. be done.

When the recording paper is printed, a print layer such as ink is formed on the surface of the resin coating of the recording paper. For example, as shown in the schematic diagram of FIG. 1, a print layer 5 is formed on the surface of the resin coating 3 of the recording paper.
From the viewpoint of protecting the printed surface, a protective layer may be further provided on the printed layer.
The protective layer is located on the outermost surface of the resin coating 3 on which the printed layer is provided. By containing silicone, the protective layer can reduce the coefficient of friction of the outermost surface and reduce damage, stains, and the like on the printed layer. Silicones are silicon compounds with polysiloxane linkages.

<Characteristics of recording paper>
The recording paper of the present invention can have the structure illustrated in FIG. 1, as described above. The resin film 3 is not only a good print-receiving layer, but also has excellent adhesion to the substrate. Further, by providing the base layer 2 on the base material 1 containing the inorganic filler and providing the resin coating 3 on the surface of moderate roughness, the adhesion between the base material 1 and the resin coating 3 is further improved. Presumed.
As shown in the following examples, the recording paper of the present invention has high adhesion, especially water-resistant adhesion, does not cause poor ink transfer on printed matter and deterioration of ink adhesion, and does not cause blocking or change in paper quality after printing. It is presumed that it will be a recording paper that does not cause

(adhesive label)
Next, the adhesive label of the present invention will be described in detail, but the description of the constituent elements described below is an example (representative example) as one embodiment of the present invention, and is not limited to these contents. .
The pressure-sensitive adhesive label of the present invention includes a laminated resin film, resin coatings disposed on both sides of the laminated resin film, and an adhesive layer.
The laminated resin film comprises a substrate made of a thermoplastic resin film, a first underlayer made of a thermoplastic resin composition arranged on one side of the substrate, and a thermoplastic resin composition arranged on the other side of the substrate. and a second underlayer made of material.

FIG. 2 shows a configuration example of an adhesive label as one embodiment of the present invention.
As shown in FIG. 2, the adhesive label 40 includes a substrate 1, a first base layer 21 made of a thermoplastic resin composition located on one side of the substrate 1, and a first base layer 21 located on the other side of the substrate 1. It has a laminated resin film 101 having a second underlayer 22 made of a thermoplastic resin composition.
The adhesive label 40 includes a resin coating 31 facing the first base layer 21 of the laminated resin film, a resin coating 32 facing the second base layer 22 of the laminated resin film, and a second lower The adhesive layer 4 is arranged on the surface opposite to the second base layer 22 with respect to the resin coating 32 arranged facing the stratum 22 .

In this specification, the laminated resin film and the resin coatings provided on both sides of the laminated resin film may be collectively referred to as recording paper. Specifically, in FIG. 2, a laminate composed of a resin coating 31, a laminated resin film (including a first base layer 21, a substrate 1, and a second base layer 22) 101, and a resin coating 32 is also referred to as a recording paper 102. say.
The adhesive label 40 is obtained by laminating the recording paper 102 and the adhesive layer 4 .

<Laminated resin film>
The laminated resin film in the pressure-sensitive adhesive label of the present invention comprises a substrate made of a thermoplastic resin film, a first underlayer made of a thermoplastic resin composition disposed on one side of the substrate, and and a second underlayer made of a thermoplastic resin composition.

<<Base material>>
In the pressure-sensitive adhesive label of the present invention, the substrate is made of a thermoplastic resin film.
The thermoplastic resin, filler and other components contained in the thermoplastic resin film are all the same as those described in the section (Recording paper), and the preferred materials and preferred contents are also the same. . The porosity of the substrate is also as described in the section (Recording paper).
The layer structure and thickness of the substrate are also as described in the section (Recording paper). The thickness of the base material is preferably 30 μm or more, more preferably 50 μm or more, since sufficient mechanical strength for use as an adhesive label can be easily obtained. The thickness is preferably 200 μm or less, more preferably 150 μm or less, from the viewpoint of reducing the weight of the label itself and improving the handleability.

<<First Underlayer and Second Underlayer>>
In the pressure-sensitive adhesive label of the present invention, the substrate has a first underlayer and a second underlayer on both sides thereof, both of which are the same as those described in the section <<Underlayer>> of (Recording Paper), A preferred embodiment is also the same. The thicknesses of the first underlayer and the second underlayer are each preferably 1 μm or more, more preferably 2 μm or more, from the viewpoint of increasing the adhesion between the substrate and the resin coating. From the viewpoint of imparting moderate roughness to the surfaces of the first underlayer and the second underlayer, the thickness of the first underlayer and the second underlayer is preferably 50 μm or less, more preferably 30 μm or less, and 20 μm or less. More preferred. The thickness of the adhesive label is preferably 200 μm or less from the viewpoint of reducing the weight of the label itself and improving the handleability. is more preferred. The types of components constituting the first underlayer and the second underlayer, their content, thickness, and indentation elastic modulus may be the same or different.
The surfaces of the first underlayer and the second underlayer, that is, the surface on which the resin coating described later is to be formed, may be subjected to surface treatment in the same manner as described in the section (Recording Paper).

<<Method for producing laminated resin film>>
In the pressure-sensitive adhesive label of the present invention, the base material of the laminated resin film, the first base layer, or the second base layer is usually molded after mixing the above-described thermoplastic resin and other components contained in the layer. can be obtained by As a molding method, the same method as described in the section (Recording paper) can be used. The stretching temperature, stretching speed, stretching ratio, etc. are also as described in the section of (Recording paper).

At least one of the base material, the first base layer, and the second base layer in the laminated resin film should be stretched from the viewpoint of giving the pressure-sensitive adhesive label an appropriate stiffness and improving workability when used as a label. is preferred. From the viewpoint of reducing the environmental load by the porosity, it is preferable that the substrate is stretched. From the viewpoint of reducing the environmental load by the porosity, it is preferable that the substrate is stretched. The substrate is preferably a porous stretched layer because pores are formed in the substrate by stretching the substrate containing the inorganic filler.
Moreover, when the substrate has a multilayer structure, at least one layer thereof is preferably stretched.
When stretching a plurality of layers, each layer may be stretched individually before lamination, or may be stretched collectively after lamination. Further, the stretched layer may be stretched again after lamination.

<<Resin Coating>>
In the pressure-sensitive adhesive label of the present invention, the resin coatings disposed on both sides of the laminated resin film contain a resin that is a reaction product of a cationic water-soluble polymer and a silane coupling agent, and do not contain thermoplastic resin particles. The resin film in the present invention is a film on which characters, images, etc., can be recorded by printing, writing instruments, or the like. Moreover, it is also a layer having good adhesiveness with an adhesive layer to be described later. Since the adhesiveness between the laminated resin film and the adhesive layer is improved by laminating with the resin film interposed therebetween, the adhesive label of the present invention has the advantage that adhesive residue is less likely to occur even if it is peeled off after being attached to another article. have.

As shown in FIG. 2, the adhesive label of the present invention has two resin coatings (resin coating 31 and resin coating 32). The types of components constituting these resin coatings and the proportions of the components may be the same or different.

The resin coating in the present invention can be formed using an aqueous solution containing a cationic water-soluble polymer and a silane coupling agent and containing no thermoplastic resin particles. Specifically, it can be formed by the same method as the method for producing the resin coating described in the section (Recording Paper). The cationic water-soluble polymer, silane coupling agent, inorganic filler, and other components (antistatic agent, cross-linking accelerator, antiblocking agent, etc.) are all the same as those described in the section (Recording paper). The same applies to preferred materials and preferred contents.
The thickness of the resin coating is as described in the section (Recording Paper), and the preferred embodiments are also the same.

<Adhesive layer>
Examples of adhesives used for the adhesive layer include adhesives such as rubber-based adhesives, acrylic-based adhesives, and silicone-based adhesives.
Rubber-based adhesives include polyisobutylene rubber, butyl rubber, and mixtures thereof, or these rubber-based adhesives are blended with tackifiers such as abietic acid rosin esters, terpene-phenol copolymers, and terpene-indene copolymers. and the like.
Examples of acrylic pressure-sensitive adhesives include those having a glass transition point of −20° C. or lower, such as 2-ethylhexyl acrylate/n-butyl acrylate copolymer and 2-ethylhexyl acrylate/ethyl acrylate/methyl methacrylate copolymer. be done.
Examples of the silicone-based pressure-sensitive adhesive include addition-curable pressure-sensitive adhesives that use a platinum compound or the like as a catalyst, and peroxide-curable pressure-sensitive adhesives that are cured with benzoyl peroxide or the like.
Examples of adhesives include those in various forms such as solution type, emulsion type, and hot-melt type.

The adhesive layer may be formed by directly applying an adhesive to the surface of the recording paper, or by applying an adhesive to the surface of a release sheet to be described later to form an adhesive layer, which is then applied to the recording paper. It may be applied to the surface.
Examples of adhesive coating apparatuses include bar coaters, blade coaters, comma coaters, die coaters, air knife coaters, gravure coaters, lip coaters, reverse coaters, roll coaters, and spray coaters. The adhesive layer is formed by smoothing the coating film of the adhesive or the like applied by these coating apparatuses, if necessary, and performing a drying process. The coating amount of the adhesive is not particularly limited, but the solid content after drying is preferably 3 g/m ² or more, more preferably 10 g/m ² or more, and preferably 60 g/m ² or less. , 40 g/m ² or less.
If necessary, the adhesive layer may have a release sheet provided on the side opposite to the side of the adhesive layer in contact with the recording paper.

<<Release sheet>>
For the purpose of protecting the surface of the adhesive layer, the release sheet is optionally provided on the surface of the adhesive layer that does not come into contact with the recording paper. As the release sheet, woodfree paper or kraft paper as it is, calendering, resin coating or film lamination on woodfree paper or kraft paper, glassine paper, coated paper, plastic film, etc. with silicone treatment, etc. can be used. Among these, it is preferable to use the one having the surface in contact with the adhesive layer subjected to silicone treatment because of its good releasability from the adhesive layer.

<How to use the adhesive label>
As described above, the resin coating is a recordable film. Examples of recording methods include printing and recording with writing instruments. The adhesive label of the present invention can be used as recording paper that can be attached to other articles by having an adhesive layer through a resin film.
The same printing method as described in the section (Recording paper) can be used. A protective layer may be provided to protect the printed layer (printed surface), and the materials for the protective layer are the same as those described above.

<Characteristics of adhesive labels>
The adhesive label of the present invention has the structure illustrated in FIG. 2, as described above. The resin film 31 is not only a good print-receiving layer, but also has excellent adhesion to the substrate. Furthermore, by providing the first base layer 21 on the base material 1 containing the inorganic filler and providing the resin coating 31 on a surface with moderate roughness, the adhesion between the base material 1 and the resin coating 31 is further improved. estimated to improve.

The resin coating 32 contributes to the adhesion between the base material 1 and the adhesive layer 4, and furthermore, the second base layer 22 is provided on the base material 1 containing the inorganic filler, and the resin coating is applied to the surface of moderate roughness. It is presumed that the adhesion between the substrate 1 and the resin coating 32 is further improved by providing the coating 32 .
Combined with these, the pressure-sensitive adhesive label of the present invention has high adhesiveness, particularly water-resistant adhesiveness, less ink transfer failure and reduced ink adhesion to printed matter, and does not cause adhesive residue, as will be shown in the examples below. It is presumed that the adhesive label will not cause blocking or change in paper quality after printing.

(in-mold label)
The in-mold label of the present invention has a laminated resin film, a heat seal layer provided on one surface of the laminated resin film, and a resin coating provided on the other surface of the laminated resin film. The laminated resin film has a substrate made of a thermoplastic resin film, and an underlayer made of a thermoplastic resin composition and having an indentation modulus within a specific range on one surface of the substrate. The resin coating is provided on the underlayer and does not contain thermoplastic resin particles. The in-mold label of the present invention may further have a printed layer formed on the resin film by printing.

The resin film enhances adhesion to ink or toner, especially water-resistant adhesion. In addition, since the resin coating has high adhesion to any kind of thermoplastic resin, it is possible to increase the adhesion to the base material only with the resin coating. By providing the base layer, the adhesion between the substrate and the base layer and between the base layer and the resin film is further enhanced. As a result, the adhesiveness between the substrate and the resin film is further enhanced, so that the water resistance of the in-mold label as a whole is improved, and excellent printability and in-mold moldability are obtained. Since the resin coating does not contain thermoplastic resin particles, blocking due to heat fusion of the thermoplastic resin particles and changes in gloss on the surface of the resin coating are also small.

When the resin container using the in-mold label of the present invention is a polyethylene terephthalate (PET) resin container, from the viewpoint of improving the adhesion between the PET resin container and the heat seal layer, the in-mold label of the present invention is further heat-sealed. It is preferable to have a resin film also on the sealing layer. PET resin has a lower melt viscosity than polyethylene resin or the like, and a stretch-blow method is used in which PET resin is heated to near the softening point instead of the melting point during molding. A low-melting resin is used for the heat seal layer so that the heat-sealing layer can be sufficiently heat-sealed even under such low-temperature molding conditions. Since it contains a cationic water-soluble polymer having a high adhesion to the PET resin. That is, the resin film increases the adhesion between the heat-seal layer and the PET resin container and improves the water resistance, so that the in-mold label is less likely to peel off when it gets wet, and is particularly useful for liquid containers such as beverages. can provide In this case, the two resin coatings may be the same or different in the kind and ratio of components constituting each resin coating, as long as the effect of the present invention is obtained.

FIG. 3 shows a configuration example of an in-mold label 50a as one embodiment of the present invention.
As shown in FIG. 3, the in-mold label 50a has a substrate 1, a base layer 2, a heat seal layer 6 and a resin coating 3. As shown in FIG. The base layer 2 is provided on one surface of the base material 1 , and the resin coating 3 is provided on the base layer 2 . The heat seal layer 6 is provided on the other surface of the base material 1 and positioned on the opposite side of the base layer 2 with the base material 1 interposed therebetween. The in-mold label 50a may have the printed layer 5 on the resin film 3 by printing.

FIG. 4 shows a configuration example of an in-mold label 50b suitable for PET resin containers. In FIG. 4, the same components as those of the in-mold label 50a of FIG. 3 are denoted by the same reference numerals.
As shown in FIG. 4, the in-mold label 50b has the base layer 2 on one side of the substrate 1 and the heat seal layer 6 on the other side, like the in-mold label 50a. The in-mold label 50 b also has a resin coating 31 on the base layer 2 and a resin coating 32 on the heat seal layer 6 . The printed layer 5 is provided on the resin coating 31 on the base layer 2 side.

Hereinafter, the laminated resin film and the resin coating on the laminated resin film may be collectively referred to as recording paper. In the example shown in FIG. 3, the base layer 2 and the base material 1 are the laminated resin film 101, and the laminate of the laminated resin film 101 and the resin coating 3 is the recording paper 10. FIG. In the example shown in FIG. 4, the base layer 2 and the base material 1 are the laminated resin film 101, and the laminated resin film 101 and the resin coating 31 are the recording paper 10. FIG.

<Laminated resin film>
In the in-mold label of the present invention, the laminated resin film has a substrate made of a thermoplastic resin film and a base layer made of a thermoplastic resin composition.

<<Base material>>
In the in-mold label of the present invention, the substrate is made of a thermoplastic resin film. The base material contains an inorganic filler, and the content thereof exceeds 45% by mass and is 80% by mass or less. By including an inorganic filler in the base material, it is possible to adjust the rigidity, whiteness and opacity of the base material. In addition, since the content of the inorganic filler is as high as more than 45% by mass, it is possible to reduce the amount of resin used and to impart appropriate roughness to the surface of the base material and the base layer of the resin coating described later. It is possible to provide an in-mold label in which the adhesiveness between the base layer and the resin film is improved, and accordingly the ink adhesiveness is less reduced.

The base material can provide the in-mold label with mechanical strength such as stiffness, water resistance, chemical resistance, and, if necessary, opacity.
The thermoplastic resin, filler and other components contained in the thermoplastic resin film are all the same as those described in the section (Recording paper), and the preferred materials and preferred contents are also the same. . The porosity of the substrate is as described in the section (Recording Paper), and the preferred embodiments are also the same.

The base material may have a single-layer structure, but preferably has a multilayer structure, and more preferably has a multilayer structure in which each layer has a unique property. For example, the substrate may have a three-layer structure of first surface layer/core layer/second surface layer, and the core layer may impart rigidity, opacity, lightness, etc. suitable for in-mold labels. At this time, the first surface layer and the second surface layer may be the same or different in the types of components constituting the two layers and the proportions of the components. For example, by making the first surface layer a layer that has a high affinity with the base layer and the second surface layer a layer that has a high affinity with the heat seal layer, the adhesion between the layers provided on both sides is improved. A high base material can be obtained. In addition, by appropriately designing the composition, thickness, etc. of the first surface layer and the second surface layer, it is possible not only to suppress the curling of the base material, but also to control the curling when used as an in-mold label within a specific range. becomes possible. In addition, by providing a solid print layer or a pigment-containing layer as a concealing layer inside the first surface layer or the second surface layer, when viewed from one side, the printing on the other side does not show through, and visibility is improved. can be improved.

The substrate may be an unstretched film or a stretched film. When the substrate has a multi-layer structure, a layer of unstretched film and a layer of stretched film can be combined, or stretched films having the same or different number of stretching axes in each layer can be combined. is preferably stretched.

The thickness of the substrate is preferably 20 μm or more, more preferably 40 μm or more, from the viewpoints of suppressing the occurrence of wrinkles during printing and facilitating fixation in a regular position when inserted into the mold. Further, from the viewpoint of suppressing strength reduction due to thinning of the container at the label boundary portion when the in-mold label is provided on the container, the thickness of the substrate is preferably 200 μm or less, more preferably 150 μm or less. Therefore, the thickness of the substrate is preferably 20-200 μm, more preferably 40-150 μm.

<<Underlayer>>
The in-mold label of the present invention has an underlayer between the base material and the resin coating described later, that is, on the surface facing the resin coating of the base material. >, and preferred embodiments are also the same.
The surface of the underlayer, that is, the surface on which the resin film described later is to be formed may be subjected to surface treatment in the same manner as described in the section (Recording Paper).

The indentation elastic modulus of the underlayer is preferably 70 MPa or more, more preferably 100 MPa or more, from the viewpoint of reducing blocking due to an increase in the adhesive strength of the underlayer during the in-mold label manufacturing process, and is compatible with the ink or toner in the printing layer. From the viewpoint of suppressing a decrease in adhesion, the pressure is preferably 1000 MPa or less, more preferably 900 MPa or less.

The thickness of the underlayer is preferably 1 μm or more, more preferably 2 μm or more, from the viewpoint of increasing the adhesion between the substrate and the resin coating. From the viewpoint of imparting appropriate roughness to the surface of the underlayer, the thickness of the underlayer is preferably 50 μm or less, more preferably 30 μm or less, and even more preferably 20 μm or less. In addition, the thickness of the in-mold label is preferably 200 μm or less from the viewpoint of reducing the weight of the label itself and improving the handleability. The following are more preferred.

<Resin coating>
In the in-mold label of the present invention, one surface of the laminated resin film, specifically, the resin coating disposed on the surface of the base layer provided on the substrate contains a cationic water-soluble polymer and a silane coupling agent. It can be formed using an aqueous solution containing no thermoplastic resin particles. Specifically, it can be formed by the same method as the method for producing the resin coating described in the section (Recording Paper).

The cationic water-soluble polymer, silane coupling agent, inorganic filler, and other components (antistatic agent, cross-linking accelerator, antiblocking agent, etc.) are all the same as those described in the section (Recording paper). The same applies to preferred materials and preferred contents. The thickness of the resin coating is as described in the section (Recording Paper), and the preferred embodiments are also the same.

Since the resin coating in the present invention provides high adhesion to the base material, the resin coating can be directly provided on the base material. is provided on the substrate. As a result, it is possible to provide an in-mold label with excellent moldability in which ink or toner is less likely to fall off after in-mold molding.

In addition, the resin film in the present invention has high adhesiveness to the heat seal layer described later, and also has high adhesiveness to the PET resin. Therefore, especially when applying the in-mold label of the present invention to a PET resin container, it is preferable to form a resin film also on the surface of the heat seal layer. In this case, the resin coating provided on the base layer and the resin coating provided on the heat-sealing layer may be different even if the types and contents of the components are the same, as long as the effect of the present invention can be obtained. good too.

<Heat seal layer>
The heat seal layer provides the in-mold label with excellent adhesion to the resin container. During in-mold molding of the container, the in-mold label is provided inside the mold so that the container and the heat seal layer face each other. The heat seal layer melts due to the heat during in-mold molding, and is heat-sealed to the surface of the container.

In-mold molding methods include a direct blow method using a raw resin parison and a stretch blow method using a raw resin preform. The direct blow method is a method in which a raw material resin is heated to a melting point or higher and melted to form a parison, and air pressure is applied to expand the parison in a mold to form a container. The stretch blow method is a method in which a preform formed in advance from a raw material resin is heated to near the softening point of the raw material resin, and the preform is stretched with a rod in a mold and air pressure is applied to expand it to form a container. is.

Resin containers made of polyethylene terephthalate (PET) are usually formed by a stretch-blow method in which PET is heated to a softening point rather than a melting point because PET has a low melt viscosity and it is difficult to maintain the shape of a parison in a molten state. Therefore, the heat-sealing of the in-mold label to the PET resin container is also performed in a heating temperature range near the softening point, not the melting point of the PET resin. In the in-mold label for PET resin containers molded in this way, compared to the direct blow method in which the label is heated to the melting point or higher, it is sufficiently melted even under low-temperature molding conditions to improve adhesion to the container. The sealing layer is preferably a thermoplastic resin film having a low melting point of 60-130°C. Since the lower the melting point, the lower the amount of heat required to obtain sufficient adhesiveness, the melting point of the thermoplastic resin used for the heat seal layer is more preferably 110° C. or lower, more preferably 100° C. or lower. In addition, the higher the melting point, the easier the film formation, and the easier it is to reduce sticking to rolls during film production. Therefore, the melting point of the thermoplastic resin is more preferably 70-110°C, more preferably 75-100°C.
The melting point can be measured by a differential scanning calorimeter (DSC).

Thermoplastic resins that can be used for the heat seal layer include, for example, low- or medium-density polyethylene with a density of 0.900 to 0.935 g/cm ³ and linear resin with a density of 0.880 to 0.940 g/cm ³ . polyethylene, ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, ethylene-alkyl acrylate copolymer, ethylene-alkyl methacrylate copolymer having alkyl groups of 1 to 8 carbon atoms, or ethylene -Polyethylene-based resins having a melting point of 60 to 130° C., such as metal salts of methacrylic acid copolymers such as Zn, Al, Li, K and Na, are preferred. Among them, low- or medium-density polyethylene or linear polyethylene having a crystallinity of 10 to 60% and a number average molecular weight of 10,000 to 40,000 as measured by an X-ray method is preferable.

From the viewpoint of improving adhesion and reducing blocking when in-mold labels are stacked, a copolymer containing a polar structural unit and a non-polar structural unit should be used as the thermoplastic resin for the heat seal layer. is preferred. Examples of such a copolymer include those described in WO 2018/062214.

In the heat seal layer, one type of thermoplastic resin may be used alone, or two or more types of thermoplastic resin may be mixed and used. In the latter case, from the viewpoint of suppressing peeling, It is preferable that the two or more resins to be mixed have high compatibility.

The heat seal layer may contain tackifiers, plasticizers, antifogging agents, lubricants, antiblocking agents, antistatic agents, antioxidants, heat stabilizers, light stabilizers, weather stabilizers, and ultraviolet absorbers as necessary. It can contain additives generally used in the field of polymers such as

The heat seal layer may have a single layer structure or a multilayer structure. In the case of a single layer structure, the thickness of the heat seal layer is preferably 0.5 μm or more, more preferably 0.7 μm or more, and even more preferably 1 μm or more, from the viewpoint of improving adhesion. On the other hand, from the viewpoint of suppressing cohesive failure inside the heat seal layer, the thickness is preferably 10 μm or less, more preferably 3 μm or less, and even more preferably 2 μm or less. Therefore, the thickness of the heat seal layer having a single layer structure is preferably 0.5 to 10 μm, more preferably 0.7 to 3 μm, even more preferably 1 to 2 μm.

When a resin coating is further provided on the heat-sealing layer, the composition of the number of oxygen atoms (O) and the number of carbon atoms (C) on the surface of the heat-sealing layer on which the resin coating is provided, from the viewpoint of improving the adhesion with the resin coating. The ratio value (O/C) is preferably 0.01 to 0.5. The composition ratio (O/C) is more preferably 0.03 or more, more preferably 0.05 or more, while it is more preferably 0.4 or less, still more preferably 0.25 or less. The composition ratio value (O/C) in the heat seal layer can be controlled within the above range by surface treatment similar to that for the substrate.

<Printing layer and protective layer>
As described above, the resin coating in the present invention is a recordable layer. Examples of recording methods include printing and recording with writing instruments. Since the in-mold label of the present invention has a heat-seal layer on the side opposite to the resin coating, it can be used as recording paper that can be attached to other articles.
The same printing method as described in the section (Recording paper) can be used. A protective layer may be provided to protect the printed layer (printed surface), and the materials for the protective layer are the same as those described above.

<Characteristics of in-mold label>
<<Thickness of in-mold label>>
The thickness of the in-mold label is preferably 25 μm or more, more preferably 45 μm or more, from the viewpoint of suppressing wrinkles of the label. Moreover, from the viewpoint of suppressing strength reduction due to thinning of the container at the label boundary portion when the in-mold label is provided on the container, the thickness is preferably 200 μm or less, more preferably 150 μm or less. Therefore, the thickness of the in-mold label is preferably 25-200 μm, more preferably 45-150 μm.

<<Glossiness>>
The glossiness of the resin film surface of the in-mold label of the present invention is preferably capable of maintaining the glossiness of the substrate surface. As the glossiness, a 75-degree specular glossiness measured according to JIS P 8142:1993 can be used.
The resin coating in the present invention is also preferable in that the change in glossiness before and after in-mold molding is small.

<<Haze>>
The haze of the in-mold label before the printing layer is provided is preferably high from the viewpoint of easy improvement of the opacity of the label and ease of production. Specifically, the in-mold label of the present invention preferably has a haze of 60% or more, more preferably 70% or more. On the other hand, the haze is preferably 95% or less, more preferably 90% or less. Here, haze refers to a value measured using a haze meter (cloudiness meter) in accordance with JIS K7136:2000.
The haze can be adjusted by the type of substrate, the thickness of the substrate, the shape of the surface of the substrate, the type of material used for the resin coating, the thickness of the resin coating, and the like.

The in-mold label of the present invention is particularly excellent in adhesion to liquid toners used in wet electrophotographic printing, and is suitable for applications involving small-lot printing and variable information printing.

(Manufacturing method of recording paper)
In the method for producing a recording paper of the present invention, the laminated resin film contains a cationic water-soluble polymer and a silane coupling agent, and if necessary, an inorganic filler is added to 100 parts by mass of the cationic water-soluble polymer component. The method is characterized by including a step of forming a resin coating on the laminated resin film by applying an aqueous solution containing no more than 9 parts by mass and containing no thermoplastic resin particles, followed by drying.
In this manner, a recording sheet having a resin coating formed on at least one surface of the laminated resin film can be produced.

The method for manufacturing the recording paper of the present invention will be described in detail below.
The recording paper of the present invention is obtained by applying a coating liquid for forming a resin film to at least one surface of the laminated resin film (the surface on which the base layer is formed), drying it, and applying the coating solution onto the laminated resin film. It can be manufactured by forming a resin coating.

The recording paper of the present invention can also be manufactured by roll-to-roll to improve productivity. Since the thickness of the resin film can be adjusted by adjusting the coating amount of the resin film-forming coating liquid, it is possible to manufacture the desired recording paper by, for example, reducing the thickness of the resin film while maintaining printability. can be done.

The coating solution for forming a resin film can be prepared by dissolving each component such as a cationic water-soluble polymer and a silane coupling agent in an aqueous solvent.
The aqueous solvent may be water, or may contain water as a main component and water-soluble organic solvents such as methyl alcohol, ethyl alcohol, isopropyl alcohol, acetone, methyl ethyl ketone, ethyl acetate, toluene and xylene. Having water as a main component means that 50 mass % or more of the whole is water. The use of an aqueous solvent facilitates process control and is preferable from the viewpoint of safety.

The total amount of the cationic water-soluble polymer and the silane coupling agent contained in the resin film-forming coating solution is 0.5% by mass or more with respect to the total amount of the resin film-forming coating solution in the present invention. is preferred, and 10% by mass or more is more preferred. Further, the total amount of the cationic water-soluble polymer and the silane coupling agent contained in the resin film-forming coating liquid of the present invention is preferably 40% by mass or less, more preferably 25% by mass or less. preferable.

The coating of the coating liquid for forming the resin film and the drying of the coating film may be performed in-line or off-line in accordance with the molding of the laminated resin film.
Coating equipment such as a die coater, bar coater, roll coater, lip coater, gravure coater, spray coater, blade coater, reverse coater, and air knife coater can be used to apply the resin film-forming coating liquid. .
The coating amount of the resin film-forming coating solution can be appropriately adjusted in consideration of the thickness of the resin film after drying, the concentration of the contained components, and the like.

A drying device such as a hot air blower or an infrared dryer can be used for drying the coating film.
By drying the coating film, the dehydration condensation reaction by the silane coupling agent in the coating film proceeds, and it is presumed that a resin, which is a reaction product of the silane coupling agent and the cationic water-soluble polymer, is produced.

(Manufacturing method of adhesive label)
The adhesive label of the present invention can be produced by forming an adhesive layer on the surface of the recording paper obtained by the method described in the section (Manufacturing method of recording paper).
More specifically, first, a first underlayer and a second underlayer are provided on both surfaces of a substrate to produce a laminated resin film. Next, a resin film-forming coating liquid is applied to both surfaces of the obtained laminated resin film, that is, the surfaces of the first underlayer and the second underlayer, and dried to form resin films on both surfaces of the substrate. Form and produce recording paper. The composition, coating method, drying method, and the like of the coating liquid for forming the resin film are the same as those described in the section (Manufacturing method of recording paper).
The adhesive may be directly applied to the surface of the resulting recording paper, or the adhesive may be applied to the surface of the release sheet described above to form an adhesive layer, which is then applied to the surface of the recording paper. may be applied to

(Manufacturing method of in-mold label)
In the method for producing an in-mold label of the present invention, the other surface of a laminated resin film provided with a heat-seal layer on one surface is coated with the above-described coating solution for forming a resin film, followed by drying. , including the step of forming a resin coating.

The in-mold label of the present invention can also be manufactured by roll-to-roll to improve productivity. Since the thickness of the resin film can be adjusted by adjusting the coating amount of the resin film-forming coating liquid in the present invention, the desired in-mold label can be produced by reducing the thickness of the resin film while maintaining printability. can do.

<Method for producing laminated resin film with heat seal layer>
A laminated resin film provided with a heat-sealing layer is obtained by laminating a heat-sealing layer and a base layer on both sides of a substrate. Lamination methods that can be used include a coextrusion method, an extrusion lamination method, a film bonding method, a coating method, and the like.
In the coextrusion method, the thermoplastic resin composition for the base material, the thermoplastic resin composition for the heat seal layer, and the thermoplastic resin composition for the base layer (each may be plural) are supplied to the multilayer die. Then, since it is laminated and extruded in a multi-layer die, lamination is performed at the same time as molding.
In the extrusion lamination method, the base material is first formed, and the molten thermoplastic resin composition for the heat seal layer and the thermoplastic resin composition for the underlayer are laminated on this, and nipped with rolls while cooling. Forming and lamination are performed in separate processes.
In the film lamination method, the base material (for example, the base material of the recording paper described above), the heat-seal layer, and the base layer are each formed into films, and the two are laminated together via a pressure-sensitive adhesive. done in the process.
In the case where the heat-seal layer has a multi-layer structure including a non-polar resin layer and a polar resin layer, the polar resin layer is provided by a coating method on the base material obtained by laminating the non-polar resin layer on one side of the base material by the above method. can be done. Examples of coating methods include solvent coating methods and water-based coating methods.
Among these methods, the co-extrusion method is preferable from the viewpoint that each layer can be firmly adhered.

Film forming methods for film forming each layer independently include extrusion molding (cast molding) using a T-die, inflation molding using an O-die, and calendering using rolling rolls. As a method for forming a film for a substrate having a multilayer structure, the above-described coextrusion method, extrusion lamination method, or the like can be used.

The substrate, heat seal layer and underlayer may be non-stretched films or stretched films.
Stretching methods include, for example, a longitudinal stretching method using a difference in circumferential speed between rolls, a transverse stretching method using a tenter oven, a sequential biaxial stretching method combining these methods, a rolling method, and a simultaneous two-stretching method using a combination of a tenter oven and a pantograph. Examples include an axial stretching method and a simultaneous biaxial stretching method using a combination of a tenter oven and a linear motor. A simultaneous biaxial stretching (inflation molding) method can also be used, in which a circular die connected to a screw extruder is used to extrude a molten resin into a tubular shape, and then air is blown into the tubular shape.

The base material and the heat-seal layer or the base layer may be stretched individually before laminating each layer, or may be stretched collectively after lamination. Further, the stretched layer may be stretched again after lamination.

When the thermoplastic resin used for each layer is an amorphous resin, the stretching temperature when stretching is preferably in the range of the glass transition temperature of the thermoplastic resin or higher. Also, when the thermoplastic resin is a crystalline resin, the stretching temperature should be above the glass transition point of the non-crystalline portion of the thermoplastic resin and below the melting point of the crystalline portion of the thermoplastic resin. is preferred, and specifically, a temperature lower than the melting point of the thermoplastic resin by 2 to 60°C is preferred.

The stretching speed is not particularly limited, but from the viewpoint of stable stretching molding, it is preferably in the range of 20 to 350 m/min.
The draw ratio for stretching the thermoplastic resin film can also be appropriately determined in consideration of the properties of the thermoplastic resin to be used. For example, when a thermoplastic resin film containing an inorganic filler is stretched in one direction, the stretch ratio is usually about 1.2 times or more, preferably 2 times or more, and usually 12 times or less. , preferably 10 times or less. The draw ratio in biaxial stretching is usually 1.5 times or more, preferably 3 times or more, and usually 60 times or less, preferably 50 times or less, in terms of area draw ratio.
If the draw ratio is within the above range, the target porosity is easily obtained, the opacity is easily improved, and the environmental load is easily reduced, which is preferable. In addition, the thermoplastic resin film tends to be less likely to break and can be stably stretched.

<Method for Forming Resin Coating>
The resin coating is formed by coating an aqueous solution containing a cationic water-soluble polymer and a silane coupling agent, and optionally an inorganic filler and containing no thermoplastic resin particles, on the underlying layer of the laminated resin film. After that, it is formed by drying.
The method for forming the resin film, including the composition of the coating liquid for forming the resin film, is the same as described in the section (Manufacturing method of recording paper).

When providing a resin coating on the heat seal layer, the resin coating may be formed in the same manner as in the case of providing on the surface of the underlying layer.

A printed layer can be provided by printing on the resin film provided on the underlayer side.

If necessary, a protective layer is provided on the outermost surface of the laminated resin film on the side opposite to the heat seal layer by applying a protective layer coating solution after providing the printed layer.

<< label processing >>
The in-mold label of the present invention is processed into a required shape and size by cutting or punching. Although cutting or punching can be performed before printing, it is preferable to perform cutting or punching after printing in terms of ease of work.

<Container with label>
By in-mold molding a resin container together with the in-mold label of the present invention, a labeled container having the in-mold label attached to the surface of the resin container can be obtained. The base layer and the resin film provided thereon can provide a labeled container in which ink or toner is less peeled off after printing or molding. Further, by providing a resin film on the heat-seal layer, it is possible to provide a container with a label that has high adhesiveness even to a PET resin different from that of the base material and is less likely to peel off.

<<Resin container>>
The material of the resin container for which the in-mold label of the present invention can be used is not particularly limited, and it can be used for resin containers such as polyethylene resin, polypropylene resin, and PET resin.

The color of the container may be transparent or a natural color that does not contain a colorant such as a pigment or dye, or may be an opaque color due to a colorant or coloring.
The cross-sectional shape of the body of the container may be a perfect circle, an ellipse, or a rectangle. If the cross-sectional shape of the fuselage is rectangular, it is preferred that the corners have curvature. From the viewpoint of strength, the cross section of the body is preferably a perfect circle or an ellipse close to a perfect circle, more preferably a perfect circle.

EXAMPLES The present invention will be described in more detail below with reference to examples, but the present invention is not limited to the following examples as long as the gist thereof is not exceeded. Descriptions of "parts", "%", etc. in the examples are based on mass unless otherwise specified.

(Measuring method)
<Layer thickness (μm)>
The total thickness (μm) of the laminated resin film of the underlayer and base material was measured using a constant pressure thickness measuring instrument (trade name: PG-01J, manufactured by Teclock Co., Ltd.) in accordance with JIS K7130:1999. In addition, the thickness (μm) of each layer in the laminated resin film was measured by cooling the sample to be measured with liquid nitrogen to a temperature of −60° C. or lower and placing the sample on a glass plate with a razor blade (Sick Japan Co., Ltd. ), product name: Proline blade) is cut at right angles to prepare a sample for cross-sectional observation, and the obtained sample is scanned with a scanning electron microscope (manufactured by JEOL Ltd., product name: JSM-6490). A cross-sectional observation was performed using the film, and the boundary line for each thermoplastic resin composition was determined from the appearance of the composition.

<Indentation modulus (MPa)>
Using a nanoindentation tester ENT-2100 made by Elionix, using a Berkovich indenter (tipped triangular pyramid) under the following conditions, load from the surface side of the base layer in the laminated resin film (that is, the side on which the resin coating is arranged) - The indentation test by the unloading test was performed 5 times for each type of layer, and the (indentation) elastic modulus (MPa) of the base layer was calculated from the average value of each test.
Temperature: 30°C
Maximum load: 0.05mN
Load speed: 0.005mN
Holding time at maximum load: 1 second Surface detection method: Inclined method Surface detection threshold coefficient: 2.0
Spring compensation: none

<Surface roughness (μm), peak count number>
The surface roughness of the underlayer (arithmetic mean roughness Ra (μm)) and peak count number (PRc) conform to JIS B0601: 2003, and are measured using a three-dimensional roughness measuring device (manufactured by Kosaka Laboratory Co., Ltd., trade name : SE-3AK) and an analyzer (manufactured by Kosaka Laboratory Ltd., trade name: SPA-11).

<Glossiness (°)>
The glossiness (°) of the surface of the resin coating of the recording paper of the present invention is preferably capable of maintaining the glossiness of the surface of the laminated resin film. As the glossiness, a 75-degree specular glossiness measured according to JIS P 8142:1993 was used.

(Preparation of resin composition)
<Preparation of resin composition (a)>
Propylene homopolymer (manufactured by Japan Polypropylene Corporation, trade name: Novatec PP FY4, MFR (230° C., 2.16 kg load): 5 g/10 minutes, melting point: 165° C.) 40 parts by mass, heavy calcium carbonate (Bihoku flour A resin composition (a) consisting of 60 parts by mass of Softon 1800 (manufactured by Kakogyo Co., Ltd., average particle diameter 1.2 μm (measurement method: air permeation method)) was prepared.

<Resin Compositions (b) to (d)>
Resin compositions (b) to (d) were prepared in the same manner as resin composition (a), except that the mixing ratio of the propylene homopolymer and ground calcium carbonate was changed as shown in Table 1.

<Preparation of resin composition (e)>
Propylene homopolymer (manufactured by Japan Polypropylene Corporation, trade name: Novatec PP FY4, MFR (230 ° C., 2.16 kg load): 5 g / 10 minutes, melting point: 165 ° C.) 58 parts by mass, high density polyethylene (Japan Polyethylene Co., Ltd. Company manufactured, product name: Novatec HD HJ360, MFR (190 ° C., 2.16 kg load): 5 g / 10 minutes, melting point: 132 ° C.) 20 parts by mass, maleic acid modified polypropylene (manufactured by Mitsubishi Chemical Corporation, product name: Modic P908, softening point: 140 ° C.) 2 parts by mass, heavy calcium carbonate (manufactured by Bihoku Funka Kogyo Co., Ltd., trade name: Softon 1800, average particle size 1.2 μm (measurement method: air permeation method)) 20 parts by mass A resin composition (e) was prepared.

<Preparation of resin composition (f)>
Resin composition (f) comprising 100 parts by mass of a propylene homopolymer (manufactured by Japan Polypropylene Corporation, trade name: Novatec PP FY4, MFR (230°C, 2.16 kg load): 5 g/10 minutes, melting point: 165°C) was prepared.

<Preparation of resin composition (g)>
Propylene-ethylene random copolymer (manufactured by Japan Polypropylene Corporation, trade name: Novatec PP FW4B, MFR (230° C., 2.16 kg load): 6.5 g/10 minutes, melting point: 140° C.) resin consisting of 100 parts by mass Composition (g) was prepared.

<Preparation of resin composition (h)>
A resin composition (h ) was prepared.

<Preparation of resin composition (i)>
Linear low-density polyethylene (manufactured by Japan Polyethylene Co., Ltd., trade name: Novatec LL UF240, MFR (190 ° C., 2.16 kg load): 2.1 g / 10 minutes, melting point: 123 ° C.) Resin composition consisting of 100 parts by mass Item (i) was prepared.

<Preparation of resin composition (j)>
Propylene homopolymer (manufactured by Japan Polypropylene Corporation, trade name: Novatec PP FY4, MFR (230° C., 2.16 kg load): 5 g/10 minutes, melting point: 165° C.) 80 parts by mass, olefin elastomer (Mitsui Chemicals Co., Ltd. A resin composition (j) consisting of 20 parts by mass of TAFUMER PN PN-3560, MFR (230° C., 2.16 kg load): 6 g/10 min, melting point: 160° C.) was prepared.

<Preparation of Resin Compositions (k) and (l)>
Resin compositions (k) and (l) were prepared in the same manner as resin composition (j), except that the blending ratio of the propylene homopolymer and olefinic elastomer was changed as shown in Table 1.

The components of resin compositions (a) to (l) are shown in Table 1 below.

(Constituents of coating solution for forming resin film)
<Cationic water-soluble polymer (A1) aqueous solution>
A reactor with an internal volume of 150 L equipped with a reflux condenser, a nitrogen inlet tube, a stirrer, a thermometer, a dropping funnel and a jacket for heating was charged with 40 kg of isopropanol (manufactured by Tokuyama, trade name: Tokuso IPA). . While stirring, 12.6 kg of N,N-dimethylaminoethyl methacrylate (manufactured by Sanyo Chemical Industries, trade name: Methacrylate DMA), 12.6 kg of butyl methacrylate (manufactured by Mitsubishi Rayon Co., Ltd., trade name: Acryester B) and a higher alcohol 2.8 kg of methacrylic acid ester (manufactured by Mitsubishi Rayon Co., Ltd., trade name: Acryester SL, a mixture of lauryl methacrylate and tridecyl methacrylate) was charged. After performing nitrogen substitution in the system and raising the internal temperature to 80 ° C., 2,2'-azobisisobutyronitrile (manufactured by Wako Pure Chemical Industries, Ltd., trade name: V-60 (AIBN )) was added to initiate polymerization.
Polymerization was carried out for 4 hours while maintaining the reaction temperature at 80° C., and the resulting copolymer was neutralized with 4.3 kg of glacial acetic acid (manufactured by Wako Pure Chemical Industries, Ltd.). While isopropanol is distilled off from the reactor, 48.3 kg of ion-exchanged water is added to replace the inside of the system, and a viscous aqueous solution (third A methacrylic polymer having a concentration of 35% by mass of a class amino group-containing methacrylic polymer was obtained. The resulting aqueous solution was used as an aqueous cationic water-soluble polymer (A1) solution.

<Cationic water-soluble polymer (A2) aqueous solution>
A commercially available polyethyleneimine aqueous solution (manufactured by BASF Japan, trade name: Polymin SK), which is a secondary amino group-containing polymer, was used as the cationic water-soluble polymer (A2) aqueous solution.

<Silane coupling agent (B)>
A commercially available silane coupling agent, 3-glycidoxypropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd., trade name: KBM-403) was used as the silane coupling agent (B).

<Antistatic agent (C)>
35 parts by mass of dimethylaminoethyl methacrylate, 20 parts by mass of ethyl methacrylate, 20 parts by mass of cyclohexyl methacrylate, and 25 parts by mass of stearyl methacrylate were placed in a four-necked flask equipped with a stirrer, reflux condenser, thermometer, and nitrogen gas inlet tube. 150 parts by weight of ethyl alcohol and 1 part by weight of 2,2'-azobisisobutyronitrile were added. After purging the inside of the system with nitrogen, a polymerization reaction was carried out at a temperature of 80° C. for 6 hours under a nitrogen stream. Then, 70 parts by weight of a 60% by weight ethyl alcohol solution of 3-chloro-2-hydroxypropylammonium chloride was added, and the mixture was reacted at a temperature of 80° C. for 15 hours. Ethyl alcohol was distilled off while water was added dropwise to obtain an aqueous solution containing a quaternary ammonium salt-containing acrylic resin having a concentration of 30% by mass, which was used as an antistatic agent (C).

<Olefin-based copolymer emulsion>
Using a twin-screw extruder (manufactured by Japan Steel Works, Ltd., machine name: TEX30HSS), melt-kneading and emulsification of the starting resin were carried out in the following procedure to prepare an olefinic copolymer emulsion.
Specifically, pellet-shaped ethylene-methacrylic acid-acrylic acid ester copolymer (manufactured by Mitsui DuPont Polychemicals, trade name: Nucrel N035C) was supplied from a hopper to an extruder as an olefin copolymer. . Then, the mixture was melted and kneaded under conditions of a screw rotation speed of 230 rpm and a cylinder temperature of 160 to 250°C.
Next, the cationic water-soluble polymer (A1) was added from the injection port at the intermediate part of the cylinder of the extruder so that 5 parts by mass of the cationic water-soluble polymer (A1) per 100 parts by mass of the olefinic copolymer. It was continuously supplied to emulsify and disperse the olefin copolymer. Then, it was extruded from the extruder outlet to obtain a milky white aqueous dispersion. Ion-exchanged water was added to this aqueous dispersion to adjust the total concentration of the cationic water-soluble polymer (A1) and the olefinic copolymer to 45% by mass, thereby obtaining an olefinic copolymer emulsion. The volume average particle diameter of the olefin copolymer particles in the emulsion was measured with a laser diffraction particle size distribution analyzer (manufactured by Shimadzu Corporation, device name: SALD-2000) and found to be 1.0 μm.

<Crosslinking agent>
An epichlorohydrin adduct of polyamine polyamide (trade name: WS-4082, manufactured by Nihon PMC Co., Ltd.) was used as a cross-linking agent other than the silane coupling agent.
<Inorganic filler>
Calcium carbonate (manufactured by Bihoku Funka Kogyo Co., Ltd., trade name: Softon 1800, average particle size 1.2 μm (measurement method: air permeation method)) was used as an inorganic filler.

(Preparation of coating solution for forming resin film)
<Preparation Example 1 of Resin Coating Liquid (a)>
The cationic water-soluble polymer (A1) 100 parts by weight (solid content conversion), cationic water-soluble polymer (A2) 20 parts by weight (solid content conversion), silane coupling agent (B) 20 parts by weight, antistatic An aqueous solution containing 20 parts by mass of the agent (C) and 2 parts by mass of an inorganic filler was prepared as a coating liquid (a) for forming a resin film.
In the resin film-forming coating liquid (a), the content of the silane coupling agent (B) with respect to the cationic water-soluble polymer A (including A1 and A2) was 17% by mass.

<Preparation Example 2 of Resin Coating Liquid (b)>
The cationic water-soluble polymer (A1) 100 parts by weight (solid content conversion), the cationic water-soluble polymer (A2) 25 parts by weight (solid content conversion), the silane coupling agent (B) 30 parts by weight, and charging An aqueous solution containing 20 parts by mass of the inhibitor (C) was prepared as the coating liquid (b) for forming the resin film.
In the resin film-forming coating liquid (b), the content of the silane coupling agent (B) with respect to the cationic water-soluble polymer A (including A1 and A2) was 24% by mass.

<Preparation Example 3 of Resin Coating Liquid (c)>
The cationic water-soluble polymer (A1) 100 parts by weight (solid content conversion), the cationic water-soluble polymer (A2) 25 parts by weight (solid content conversion), the silane coupling agent (B) 40 parts by weight, and charging An aqueous solution containing 20 parts by mass of an inhibitor (C) and 5 parts by mass of an inorganic filler was prepared as a coating liquid (c) for forming a resin film.
In the resin film-forming coating liquid (c), the content of the silane coupling agent (B) with respect to the cationic water-soluble polymer A (including A1 and A2) was 32% by mass.

<Preparation Example 4 of Resin Coating Liquid (d)>
As shown in Table 2, 5 parts by mass of cationic water-soluble polymer (A2), 5 parts by mass of silane coupling agent (B) and 5 parts by mass of silane coupling agent (B) are added to 100 parts by mass of olefin copolymer emulsion (in terms of solid content). An aqueous solution containing 5 parts by mass of (C) and 2 parts by mass of an inorganic filler was prepared as a coating liquid (d) for forming a resin film.
In the resin film-forming coating liquid (d), the content of the silane coupling agent (B) with respect to the cationic water-soluble polymer A (including A1 and A2) was 100% by mass.

<Preparation Example 5 of Resin Coating Liquid (e)>
In the resin film-forming coating liquid (d), the resin film was formed except that the olefin copolymer emulsion was not used and 5 parts by weight of the cross-linking agent was used instead of 5 parts by weight of the silane coupling agent (B). A resin film-forming coating liquid (e) was prepared in the same manner as the forming coating liquid (d).
In the resin film-forming coating liquid (e), the content of the silane coupling agent (B) with respect to the cationic water-soluble polymer A (including A1 and A2) was 0% by mass.

<Preparation Example 6 of Resin Coating Liquid (f)>
A resin film-forming coating solution (f) was prepared in the same manner as the resin film-forming coating solution (b), except that 12 parts by mass of the inorganic filler was contained in the resin film-forming coating solution (b). Prepared as
In the resin film-forming coating liquid (f), the content of the silane coupling agent (B) with respect to the cationic water-soluble polymer A (including A1 and A2) was 24% by mass.

<Preparation Example 7 of Resin Coating Liquid (g)>
The cationic water-soluble polymer (A1) 50 parts by weight (solid content conversion), cationic water-soluble polymer (A2) 50 parts by weight (solid content conversion), silane coupling agent (B) 45 parts by weight, antistatic An aqueous solution containing 20 parts by mass of the agent (C) and 0.1 parts by mass of an inorganic filler was prepared as a coating liquid (g) for forming a resin film.
In the resin film-forming coating liquid (g), the content of the silane coupling agent (B) with respect to the cationic water-soluble polymer A (including A1 and A2) was 45% by mass.

<Preparation Example 8 of Resin Coating Liquid (h)>
The cationic water-soluble polymer (A1) 40 parts by weight (solid content conversion), cationic water-soluble polymer (A2) 60 parts by weight (solid content conversion), silane coupling agent (B) 53 parts by weight, antistatic An aqueous solution containing 30 parts by mass of the agent (C) and 0.1 parts by mass of an inorganic filler was prepared as a coating liquid (h) for forming a resin film.
In the resin film-forming coating liquid (h), the content of the silane coupling agent (B) with respect to the cationic water-soluble polymer A (including A1 and A2) was 53% by mass.

<Preparation Example 9 of Resin Coating Liquid (i)>
In the resin film-forming coating liquid (h), the content of the silane coupling agent (B) was 60 parts by mass, the content of the antistatic agent (C) was 15 parts by mass, and the content of the inorganic filler was 1.5 parts by mass. A resin film-forming coating solution (i) was prepared in the same manner as the resin film-forming coating solution (h), except that the content was 0 parts by mass.
In the resin film-forming coating liquid (i), the content of the silane coupling agent (B) with respect to the cationic water-soluble polymer A (including A1 and A2) was 60% by mass.

<Preparation Example 10 of Resin Coating Liquid (j)>
In the resin film-forming coating liquid (h), the content of the silane coupling agent (B) was 65 parts by mass, the content of the antistatic agent (C) was 15 parts by mass, and the content of the inorganic filler was 1.5 parts by mass. A resin film-forming coating solution (j) was prepared in the same manner as the resin film-forming coating solution (h), except that the content was 0 parts by mass.
In the resin film-forming coating liquid (j), the content of the silane coupling agent (B) with respect to the cationic water-soluble polymer A (including A1 and A2) was 65% by mass.

Preparation Examples 1 to 6 of the resin film-forming coating solutions (a) to (j) are shown in Table 2 below.

[Manufacturing example of recording paper]
(Manufacturing of laminated resin film)
<Production Example 1-1 of Laminated Resin Film>
After melt-kneading the resin composition (a) in an extruder set to 230 ° C., it is supplied to an extrusion die set to 250 ° C. and extruded into a sheet, which is cooled to 60 ° C. by a cooling device and unstretched. got a sheet. This non-stretched sheet was heated to 135° C. and stretched 5 times in the machine direction using the difference in peripheral speed of the roll group.
Next, the resin composition (g) was melt-kneaded in an extruder set at 250° C., extruded into a sheet, and laminated on the first surface of the resin layer composed of the resin composition (a).
Next, the resin composition (a) is melt-kneaded in an extruder set at 250 ° C., extruded into a sheet shape, and the first surface of the resin layer made of the resin composition (a) previously formed Laminated on the opposite second side.
Thus, a laminated sheet was obtained in which three layers were laminated: a resin layer made of the resin composition (g), a resin layer made of the resin composition (a), and a resin layer made of the resin composition (a). .
Next, the three-layer laminated sheet is cooled to 60° C., heated to about 150° C. using a tenter oven, stretched 8.5 times in the horizontal direction, and then heated to 160° C. for heat treatment. went.
Next, it was cooled to 60° C., and the edge was slit so that the thickness was 90 μm, the resin composition (g/a/a) of each layer, the thickness of each layer (5 μm/70 μm/15 μm), the number of stretching axes of each layer (1 axis/2 An axial/uniaxial) laminated resin film was obtained.
In this laminated resin film, the resin layer made of the resin composition (g) corresponds to the base layer. Further, this laminated resin film has a base material consisting of two layers, a layer made of the biaxially stretched resin composition (a) is a core layer, and a layer made of the uniaxially stretched resin composition (a) layer corresponds to the surface layer.

<Production Examples 1-2 to 1-6, 1-8 to 1-21 of laminated resin films>
Laminated resin film production example 1-1- Laminated resin films of 2 to 1-6 and 1-8 to 1-21 were obtained.

<Production Example 1-7 of Laminated Resin Film>
After melt-kneading the resin composition (a) in an extruder set to 230 ° C., it is supplied to an extrusion die set to 250 ° C. and extruded into a sheet, which is cooled to 60 ° C. by a cooling device and unstretched. got a sheet. This non-stretched sheet was heated to 135° C. and stretched 5 times in the machine direction using the difference in peripheral speed of the roll group.
Next, the resin layer made of the resin composition (a) is cooled to 60°C, heated to about 150°C using a tenter oven, stretched 8.5 times in the transverse direction, and then heated to 160°C. A heat treatment was performed.
Then, the film was cooled to 60° C., and the tabs were slit to obtain a single-layer biaxially oriented sheet with a thickness of 70 μm.
Next, the resin composition (f) is melt-kneaded by two extruders set at 250° C., extruded into a sheet, and laminated on the first surface of the resin layer composed of the resin composition (a). At the same time, it was laminated on the second surface to obtain a laminated sheet in which three layers were laminated.
Then, it is cooled to 60° C., the edge is slit, and the thickness is 90 μm, the resin composition of each layer (f / a / f), the thickness of each layer (10 μm / 70 μm / 10 μm), the number of stretching axes of each layer (unstretched / 2 A laminated resin film of axial/non-stretching was obtained.
In this laminated resin film, the resin layer made of the resin composition (f) laminated on the first surface of the resin layer made of the biaxially stretched resin composition (a) corresponds to the base layer. In addition, this laminated resin film has a substrate consisting of two layers, a layer made of the biaxially stretched resin composition (a) is a core layer, and a layer made of the biaxially stretched resin composition (a) The layer composed of the resin composition (f) laminated on the second surface of the resin layer corresponds to the surface layer.

The results of measurements for each laminated resin film are shown in Table 3A below.

(Manufacture of recording paper)
<Example 1-1>
Both surfaces of the laminated resin film obtained in Production Example 1-1 of the laminated resin film were subjected to corona discharge treatment under the conditions of 30 W min/m ² , and then the thickness of each surface after drying was 0.03 μm. Then, the resin film-forming coating solution (a) prepared in Preparation Example 1-1 of the resin film-forming coating solution was applied by a roll coater. The coating film was dried in an oven at 60° C. to form a resin film, and recording paper was obtained.

<Examples 1-2 to 1-13 and Comparative Examples 1-1 to 1-8>
Examples 1-2 to 1-13 and Comparative Example 1 were prepared in the same manner as in Example 1-1, except that the laminated resin film and the resin coating were changed as shown in Table 3B below. -1 to 1-8 recording sheets were obtained.

Table 3B below shows the measurement results for each recording sheet.

(evaluation)
The recording papers obtained in Examples 1-1 to 1-7, 1-9 to 1-13, and Comparative Examples 1-1 to 1-4 and 1-6 to 1-8 were evaluated as follows. Ta.

<Anti-blocking property 1>
The recording paper obtained in each example and comparative example was wound into a roll and stored for 1 day in an atmosphere of 40° C. and 50% relative humidity. Whether smooth drawing was possible or not was evaluated for winding blocking by the following method.
○: Pull out smoothly with no peeling sound △: There is peeling sound, but the appearance of the laminated resin film after collection is not impaired (practical lower limit)
×: There is a loud peeling sound, and the appearance of the laminated resin film after being taken off is damaged (not suitable for practical use).

<Anti-blocking property 2>
Two sheets each of the recording papers obtained in each example and comparative example were stacked so that the resin coatings were in contact with each other, and sandwiched in a thermal gradient tester (TYPE HG-100, manufactured by Toyo Seiki Seisakusho Co., Ltd.). The temperature was set to 50° C. in increments of 5° C. for 5 minutes, and hot roll fusion bondability was evaluated according to the following evaluation criteria.
○: No adhesion at 40 ° C or higher and 50 ° C or lower △: No adhesion at 30 ° C or higher and lower than 40 ° C (practical lower limit)
×: Bonded at less than 30 ° C. (not suitable for practical use)

(Printability of wet electrophotographic printing method)
Next, the recording papers obtained in Examples 1-1 to 1-7, 1-9 to 1-13, Comparative Examples 1-1 to 1-4 and 1-6 to 1-8 were subjected to the following method. Printability was evaluated.

First, the recording paper obtained in each example and comparative example was conditioned for 3 hours in an environment of a temperature of 23° C. and a relative humidity of 50%. Next, in the same environment as in the humidity conditioning, a wet electrophotographic printer (manufactured by HP Japan, machine name: Indigo7800) was used to print a solid black image with a density of 100% and black with a density of 30% on one side of the recording paper. A dot pattern was printed. The printer was equipped with multiple color liquid toners (manufactured by Hewlett-Packard Japan, product names: HP ElectroInk Light Cyan Q4045A, HP ElectroInk Light Magenta Q4046A, HP ElectroInk Digital Matt 4.0,3 Cartridges Q4037A, HP ElectroInk Digital Matt 4.0,9). Cartridges Q4038A).

<Toner Transferability>
The state of the image on the recording paper after the printing was magnified with a loupe and visually observed, and the toner transfer property was evaluated as follows.
○: The image is clear and the toner transfer property is good. △: Ink bleeding is unclear visually, but the dot area is widened when observed with a magnifying glass (lower limit for practical use).
x: The image is blurred, and the transferability of the toner is low (not suitable for practical use).

<Toner adhesion>
After the recording paper printed by the above procedure was immersed in water at 23°C for 24 hours, it was removed from the water and the moisture was lightly wiped off with a waste cloth. , trade name: Sellotape (registered trademark) CT-18) was adhered to the adhesive side, and rubbed three times with a finger to ensure sufficient adhesion. After manually peeling the adhered cellophane tape at a speed of 300 m / min in the direction of 180 degrees, using a small general-purpose image analysis device (manufactured by Nireco, model name: LUZEX-AP), the residual rate of ink on the recording paper was calculated. Specifically, an image obtained by photographing the printed surface was subjected to binarization processing, and the ratio of the area occupied by the toner was calculated as the residual ratio. Based on the calculated residual ratio of ink, the adhesion of the ink was ranked according to the following criteria.
◯: Toner residual rate is 90% or more △: Toner residual rate is 70% or more and less than 90% (practical lower limit)
×: Less than 70% residual toner (unsuitable for practical use)

<Scratch resistance: Wet A>
The recording paper printed in the above procedure is attached to a Gakushin type dyeing friction fastness tester (manufactured by Suga Test Instruments Co., Ltd., device name: friction tester II type), and a white cotton cloth moistened with water is used to apply a load. A friction test was conducted by rubbing 100 times with 500 g. The abrasion resistance was evaluated from the percentage of toner remaining on the recording paper after the friction test, using the same criteria as the evaluation of toner adhesion.

<Scratch resistance: Wet B>
After the recording paper printed by the above procedure was immersed in water at 23°C for 24 hours, it was removed from the water and the moisture was lightly wiped off with a waste cloth. and evaluated.

<Change in gloss during printing>
One sheet of recording paper is sandwiched between a thermal gradient tester (TYPE HG-100, manufactured by Toyo Seiki Seisakusho Co., Ltd.) so that the printed surface is pressed, and the temperature is set from 90 to 170 ° C. in increments of 20 ° C. for 5 seconds. pressurized. Measure the 75-degree specular glossiness of the pressurized area in accordance with JIS P 8142:1993, and determine the glossiness change during printing from the difference from the glossiness of the unpressurized recording paper according to the following evaluation criteria. did.
○: 130 ° C. or higher and lower than 170 ° C., glossiness difference of less than 5% △: 100 ° C. or higher and lower than 130 ° C., glossiness difference of less than 10% (practical lower limit)
×: Less than 100 ° C., glossiness difference of 10% or more (not suitable for practical use)

<Light resistance>
In applications such as posters, peeling of the UV ink printed matter may occur due to outdoor use, which may be a problem. However, weather resistance evaluation results tend to fluctuate due to various variable factors such as climate and weather when exposure tests are actually performed outdoors. In this specification, printed materials were subjected to accelerated weather resistance treatment (exposure test) under uniform conditions in accordance with JIS K-7350-4, and then evaluated for adhesion to UV ink printed materials. More specifically, the acceleration treatment was performed under the following conditions.

Ultra-accelerated weathering tester (manufactured by Daipla Wintes Co., Ltd., trade name "Metal Weather KU-R5N-A", metal halide lamp type) and a glass filter "KF-2 Filter" (product name) was used. Aluminum foil tape "AL-T" (Takeuchi Industry Co., Ltd.) , trade name) was attached to a stainless steel plate (100 mm×200 mm) and fixed, and this was installed in the tester. The irradiance on the surface of the test piece was set at 90 W/m ² and the black panel temperature was set at 63°C. Two cycles of accelerated treatment were carried out, one cycle being 5 hours of exposure at a temperature of 63° C. and 50% relative humidity and the other being 3 hours of exposure at a temperature of 30° C. and 98% relative humidity. The radiation exposure on the printed surface was therefore 5.18×10 ⁶ J/m ² .
Then, the test piece subjected to the accelerated weather resistance treatment was subjected to the friction test and evaluation in the same manner as in the case of wet A for abrasion resistance.

The evaluation results of Examples 1-1 to 1-7, 1-9 to 1-13, Comparative Examples 1-1 to 1-4 and 1-6 to 1-8 are shown in Table 4 below.

(Printability of water-based inkjet printing method)
The recording papers obtained in Examples 1-8 and Comparative Examples 1-5 were evaluated for printability by the water-based inkjet printing method.
<Amount of water absorption> is measured using blank recording paper, and other than that is measured using a water-based pigment inkjet printer (model name: TM-C3500, manufactured by Seiko Epson) and standard cyan, magenta, yellow, and black water-based pigments for the printer. Using the ink (model number: SJIC22), the printability of the water-based inkjet printing system was evaluated.

<Amount of water absorption>
The water absorption amount of the resin film was measured for the recording papers obtained in Example 1-8 and Comparative Example 1-5. The amount of water absorption is obtained by measuring the amount of water absorption after contact for 120 seconds using a Cobb size measuring instrument (manufactured by Kumagai Riki Kogyo Co., Ltd.) in accordance with the Cobb method (JIS P8140: 1998). The average value of the data was used as the measured value.

<Bleeding>
The recording papers obtained in Example 1-8 and Comparative Example 1-5 were printed with JIS X9201: 2001 (high-definition color digital standard image (CMYK/SCID)) on one side of the recording paper using the above printing machine. A pattern of N5 was printed by an inkjet method. The image printed by the water-based pigment ink jet printer was visually observed immediately after printing, and the dots of the image were observed under a microscope to determine bleeding as follows.
○: No bleeding at all △: The outline of the line becomes thicker or unclear, and bleeding is seen in places (lower limit for practical use)
×: Bleeding is observed in the entire image (not suitable for practical use)

<Drying property>
Immediately after printing, paper was pressed against the image printed by the above procedure, and the dryness of the ink was determined as follows.
○: The ink cannot be seen as a liquid on the surface, and even if the paper is lightly pressed, the ink does not transfer to the paper at all. Transfer (practical lower limit)
×: Ink can be seen as a liquid on the surface (not suitable for practical use)

<Scratch resistance>
One day after printing, the image portion printed by the above procedure was cut into a size of 30 mm×120 mm, and set in a Gakushin Tester (manufactured by Suga Test Instruments Co., Ltd.). As an evaluation under dry conditions, gauze dried at normal temperature was attached to a weight of 215 g, and the surface of the printed image portion was rubbed 100 times with this weight, and the degree of ink peeling was evaluated by visual observation. As an evaluation under wet conditions, gauze impregnated with 20 μL of pure water at room temperature was attached to a weight of 215 g. It was evaluated by observation. The evaluation criteria are the same under dry conditions and wet conditions, and are the evaluation criteria shown below.
◯: Residual rate of rubbed image portion is 95% or more △: Residual rate of rubbed image portion is 80% or more and less than 95% (practical lower limit)
×: Residual rate of rubbed image portion is less than 80% (not suitable for practical use)

The evaluation results of Examples 1-8 and Comparative Examples 1-5 are shown in Table 5 below.

As shown in Table 4, the recording papers of Examples are printable in terms of toner transferability, toner adhesion, and abrasion resistance even when printing is performed by a wet electrophotographic printing method using a liquid toner. was confirmed to be good. Good results are obtained even under wet conditions, indicating that the film is particularly excellent in water resistance. Moreover, since the recording papers of Examples are excellent in anti-blocking property and weather resistance, it is found that blocking and changes in paper quality hardly occur when printed matter is stored at high temperatures. Furthermore, it was confirmed that the change in gloss before and after printing was small.
In addition, as shown in Table 5, the recording papers of Examples had good printability in terms of bleeding, drying property, and abrasion resistance even when printing was performed by the water-based inkjet printing method, and blocking occurred. confirmed to be difficult. The resin content in the base material can also be reduced, and the environmental load can be reduced.
That is, the recording papers of Examples can reduce the environmental burden, have high adhesion, especially water-resistant adhesion, do not cause poor ink transfer on printed matter and decrease in ink adhesion, and block and after printing It can be seen that the recording paper has no change in paper quality.

On the other hand, when the recording paper of the comparative example contains the olefin copolymer particles, the toner transferability and adhesion are obtained, but the adhesion is lowered under wet conditions, and the water resistance and weather resistance are lowered. was confirmed. In addition, a resin film containing neither a silane coupling agent nor a cationic water-soluble polymer does not have sufficient printability in any printing method.
Also, a resin film containing an excessively large amount of the silane coupling agent component was too hard, and stress was concentrated on the interface between the resin film and the toner, resulting in insufficient toner adhesion.

FIGS. 5 and 6 show, respectively, the recording paper of Comparative Example 1-3, the recording paper of Example 1-1, and the surface of the laminated resin film before forming the resin coating, after depositing gold on the surface, and then scanning electron microscope. Shows a photo taken by The photograph in FIG. 5 was taken using a scanning electron microscope (model number: SM-200) manufactured by Topcon Corporation, and the photograph in FIG. 6 was taken using a scanning electron microscope (model number: JCM-6000) manufactured by JEOL Ltd. . Magnification at the time of photographing is 3000 times.
As shown in FIG. 5, Comparative Example 1-3 has many fine irregularities on the surface and is easily fluffed. This unevenness is considered to be derived from the olefinic copolymer particles. On the other hand, as shown in FIG. 6, Example 1-1 has a uniform surface with few irregularities, and has a surface structure that is less likely to become fuzzy. The particulate matter confirmed in FIG. 6 is considered to be filler in the laminated resin film.

[Example of adhesive label]
(Manufacturing of laminated resin film)
<Production example 2-1 of laminated resin film>
After melt-kneading the resin composition (a) in an extruder set to 230 ° C., it is supplied to an extrusion die set to 250 ° C. and extruded into a sheet, which is cooled to 60 ° C. by a cooling device and unstretched. got a sheet. This non-stretched sheet was heated to 135° C. and stretched 5 times in the machine direction using the difference in peripheral speed of the roll group.
Next, the resin composition (h) was melt-kneaded in an extruder set at 250° C., extruded into a sheet, and laminated on the first surface of the resin layer composed of the resin composition (a).
Next, after melt-kneading the resin composition (g) with an extruder set at 250° C., it is extruded into a sheet, and the first surface of the resin layer made of the resin composition (a) is opposite to the first surface. Laminated on two sides.
In this way, a laminated sheet was obtained in which three layers were laminated: a resin layer made of the resin composition (h), a resin layer made of the resin composition (a), and a resin layer made of the resin composition (g). .
Next, the three-layer laminated sheet is cooled to 60° C., heated to about 150° C. using a tenter oven, stretched 8.5 times in the horizontal direction, and then heated to 160° C. for heat treatment. went.
Next, it was cooled to 60° C., and the ears were slit so that the thickness was 90 μm, the resin composition of each layer (h/a/g), the thickness of each layer (10 μm/70 μm/10 μm), the number of stretching axes of each layer (1 axis/2 An axial/uniaxial) laminated resin film was obtained.
With respect to the laminated resin film, the adhesive layer was arranged on the side of the resin layer composed of the resin composition (g) as described later. That is, in the laminated resin film, the resin layer made of the resin composition (h) corresponds to the first underlayer, and the resin layer made of the resin composition (g) corresponds to the second underlayer.

<Production example 2-2 of laminated resin film>
After melt-kneading the resin composition (a) in an extruder set to 230 ° C., it is supplied to an extrusion die set to 250 ° C. and extruded into a sheet, which is cooled to 60 ° C. by a cooling device and unstretched. got a sheet. This non-stretched sheet was heated to 135° C. and stretched 5 times in the machine direction using the difference in peripheral speed of the roll group.
Next, the resin composition (h) is melt-kneaded by two extruders set at 250° C., extruded into a sheet, and laminated on the first surface of the resin layer composed of the resin composition (a). At the same time, the second surface was also laminated to obtain a laminated sheet in which three layers were laminated.
Next, the three-layer laminated sheet is cooled to 60° C., heated to about 150° C. using a tenter oven, stretched 8.5 times in the horizontal direction, and then heated to 160° C. for heat treatment. went.
Then, it is cooled to 60° C., the edge part is slit, the thickness is 90 μm, the resin composition (h/a/h) of each layer, the thickness of each layer (10 μm/70 μm/10 μm), the number of stretching axes of each layer (1 axis/2 An axial/uniaxial) laminated resin film was obtained.

<Production Examples 2-3 to 2-6 and 2-8 to 2-13 of laminated resin films>
Laminated resin film production example 2-2 was produced in the same manner as in laminated resin film production example 2-2, except that each resin layer was changed as shown in Table 6 below. Laminated resin films of 3 to 2-6 and 2-8 to 2-13 were obtained.

<Production Example 2-7 of Laminated Resin Film>
After melt-kneading the resin composition (f) with an extruder set at 230 ° C., it is supplied to an extrusion die set at 250 ° C. and extruded into a sheet, which is cooled to 60 ° C. by a cooling device and unstretched. got a sheet. This non-stretched sheet was heated to 135° C. and stretched 5 times in the machine direction using the difference in peripheral speed of the roll group.
Next, the resin layer made of the resin composition (f) is cooled to 60°C, heated to about 150°C using a tenter oven, stretched 8.5 times in the transverse direction, and then heated to 160°C. A heat treatment was performed.
Then, the film was cooled to 60° C., and the tabs were slit to obtain a single-layer biaxially oriented sheet with a thickness of 70 μm.
Next, the resin composition (f) is melt-kneaded by two extruders set at 250° C., extruded into a sheet, and a single biaxially stretched sheet of a resin layer composed of the resin composition (f). At the same time, the second surface was laminated to obtain a laminated sheet in which three layers were laminated.
Next, it is cooled to 60 ° C., the edge part is slit, the thickness is 90 μm, the resin composition of each layer (f / f / f, each layer thickness (10 μm / 70 μm / 10 μm), each layer stretching axis number (non-stretching / biaxial / non-stretching) laminated resin film was obtained.

The results of measurements of the laminated resin films obtained in Production Examples 2-1 to 2-13 are shown in Table 6 below.

(Manufacture of recording paper)
<Manufacturing Example 2-1 of Recording Paper>
After both surfaces of the laminated resin film obtained in Production Example 2-1 were subjected to corona discharge treatment under the conditions of 30 W min/m ² , the thickness of each surface after drying was 0.03 μm. The resin film-forming coating solution (a) prepared in 1 was applied using a roll coater. The coating film was dried in an oven at 60° C. to form a resin film, thereby obtaining recording paper manufactured according to Recording Paper Production Example 2-1.

<Recording Paper Production Examples 2-2 to 2-19>
Recording Paper Production Example 2-1 was prepared in the same manner as Recording Paper Production Example 2-1 except that the laminated resin film and the resin coating were changed as shown in Table 7 below 2 to 2-19 recording papers were obtained.

Recording paper production examples 2-1 to 2-19 are shown in Table 7 below.

(Manufacturing example of adhesive label)
<Example 2-1>
Silicone-treated glassine paper (G7B, Oji Tac Co., Ltd.) was used as a release sheet, and a solvent-based acrylic adhesive (Oribain BPS1109, Toyochem Co., Ltd.) and isocyanate-based cross-linking were applied to the silicone-treated surface of the glassine paper. A mixed solution obtained by mixing an agent (Oribain BHS8515, manufactured by Toyochem Co., Ltd.) and toluene at a ratio of 100:3:45 was coated with a comma coater so that the basis weight after drying was 25 g / m ² , It dried to form an adhesive layer.
Next, the laminated resin film is laminated so that the second base layer side of the laminated resin film is in contact with this adhesive layer, and the recording paper obtained in Recording Paper Production Example 2-1 and the glassine paper are pressure-bonded with a pressure roller to record. An adhesive layer was formed on the paper to obtain an adhesive label of Example 2-1.

<Examples 2-2 to 2-12 and Comparative Examples 2-1 to 2-7>
In Example 2-1, as shown in Table 8, Example 2 except that the recording paper obtained in Production Example 2-1 was changed to the recording paper obtained in Production Examples 2-2 to 2-19. Adhesive labels of Examples 2-2 to 2-12 and Comparative Examples 2-1 to 2-7 were obtained in the same manner as in -1.

(evaluation)
The adhesive labels obtained in Examples 2-1 to 2-12 and Comparative Examples 2-1 to 2-7 were tested for antiblocking property 1, antiblocking property 2, and toner transfer in the same manner as for the recording paper described above. Properties, toner adhesion, abrasion resistance (wet A), abrasion resistance (wet B), and gloss change during printing were evaluated. However, printing was performed on the surface (resin film surface) opposite to the adhesive layer forming surface of the adhesive label.

The adhesive labels obtained in Examples 2-1 to 2-12 and Comparative Examples 2-1 to 2-7 were evaluated for lamination properties and adhesive residue properties by the following methods.

<Lamination property>
A PET film was laminated using a cold lamination method on the printed surface of the pressure-sensitive adhesive label printed by the above procedure. The PET film used here has an adhesive formed on one side (trade name Proshield Cold UV-HG50, manufactured by Jetgraph Co., Ltd.), and the lamination process is performed at 23 ° C. to stick the adhesive surface of the PET film. It was carried out by superimposing on the printing surface of the label and pressing. They were then immersed in water at 23°C for 24 hours. After 5 minutes, the PET film was slowly peeled off by hand. By visually observing the state of the printed surface after peeling off the PET film, lamination properties were evaluated according to the following criteria.
○: No peeling of toner was observed △: 30% or more and less than 50% of the PET film peeled toner was transferred to the PET film side (practical lower limit)
×: 50% or more of the toner in the peeled portion of the PET film is transferred to the PET film side (not suitable for practical use)

<Adhesive residue>
The release sheet of the adhesive label was peeled off, and the adhesive layer surface was adhered to a transparent and highly smooth glass plate, and was rubbed three times with fingers to adhere sufficiently. Next, the glass plate to which the adhesive label was adhered was subjected to heat treatment for 24 hours in an environment at a temperature of 40° C., and then immersed in water at 23° C. for 24 hours. Next, after 5 minutes of taking out from the water and lightly wiping off moisture with a waste cloth, the adhered pressure-sensitive adhesive label was peeled off by hand in a direction of 180 degrees at a speed of 300 m/min. The haze of the portion of the glass plate where the adhesive label was peeled off was measured according to JIS K7136:2000 using a haze meter (manufactured by Nippon Denshoku Industries Co., Ltd., model name: NDH2000). From the difference between the measured haze and the haze of the solid glass plate, the adhesive residue property of the adhesive was determined according to the following criteria.
○: Haze difference is less than 5% △: Haze difference is 5% or more and less than 10% (practical lower limit)
×: Haze difference is 10% or more (not suitable for practical use)

Evaluation results of the adhesive labels obtained in Examples 2-1 to 2-12 and Comparative Examples 2-1 to 2-7 are shown in Table 8 below.

As is clear from Table 8, the adhesive labels of Examples 2-1 to 2-12 had excellent toner transferability, toner adhesion, and abrasion resistance even when printing was performed by a wet electrophotographic printing method using a liquid toner. Good printability was confirmed in all of the properties. As for the toner adhesion, the results are good even under wet conditions, and the water-resistant adhesion is particularly high. The resin content in the base material can also be reduced, and the environmental load can be reduced.
Further, it was confirmed that the adhesive labels of Examples 2-1 to 2-12 did not cause adhesive residue, and did not cause blocking and change in paper quality after printing.

[Example of in-mold label]
(Preparation of resin composition)
In addition to the resin compositions (a) to (l) described above, the following resin composition (m) was prepared.

<Preparation of resin composition (m)>
Propylene-ethylene random copolymer (manufactured by Japan Polypropylene Corporation, trade name: Novatec PP FW4B, MFR (230° C., 2.16 kg load): 6.5 g/10 minutes, melting point: 140° C.) 30 parts by mass, long chain Shaped low-density polyethylene (manufactured by Japan Polyethylene Co., Ltd., trade name: Novatec LL UF240, MFR (190 ° C., 2.16 kg load): 2.1 g / 10 minutes, melting point: 123 ° C.) Resin composition consisting of 70 parts by mass ( m) was prepared.

Constituent components of the resin compositions (a) to (m) used in the following examples and comparative examples are shown in Table 9 below.

(Production of laminated resin film with heat seal (HS) layer)
<Production example 3-1 of laminated resin film with HS layer>
After melt-kneading the resin composition (a) in an extruder set to 230 ° C., it is supplied to an extrusion die set to 250 ° C. and extruded into a sheet, which is cooled to 60 ° C. by a cooling device and unstretched. got a sheet. This unstretched sheet was heated to 135° C. and stretched 5 times in the longitudinal direction by utilizing the difference in peripheral speed of the roll group to obtain a uniaxially stretched sheet. Then, after melt-kneading the resin composition (g) with an extruder set at 250° C., it is extruded into a sheet and laminated on one side of the uniaxially stretched sheet, and at the same time resin composition (i) is added. After melt-kneading with an extruder set at 250° C., it is extruded into a sheet and laminated on the other side of the uniaxially oriented sheet, and a metal cooling roll and a matte rubber roll having #150 line gravure embossing. led between The embossed pattern is transferred to the thermoplastic resin side while pressing between the metal cooling roll and the matte rubber roll to bond them together, cooling to room temperature with the cooling roll, and using the resin composition (g). A three-layer laminate sheet was obtained in which the formed layer, the layer formed using the resin composition (a), and the layer formed using the resin composition (i) were laminated in this order.

The resulting three-layer laminate sheet is cooled to 60°C, heated to about 150°C using a tenter oven, stretched 8.5 times in the transverse direction, and then heated to 160°C for heat treatment. did Next, it is cooled to 60 ° C., the edge is slit, and the resin composition of each layer is (g / a / i), the thickness of all layers is 90 μm, the thickness of each layer is (15 μm / 70 μm / 5 μm), and each layer is stretched. A laminated resin film with an HS layer having the number of axes (1 axis/2 axes/1 axis) was obtained. In the obtained laminated resin film with the HS layer, the layer formed using the resin composition (i) is the heat seal layer, the layer formed using the resin composition (g) is the base layer, and the resin composition ( The layer formed using a) corresponds to the substrate.

<Production Examples 3-2 to 3-6 and 3-8 to 3-20 of laminated resin films with HS layer>
Production Examples 3-2 to 3-6 and 3-2 to 3-6 and 3-3 were produced in the same manner as in Production Example 3-1 for the HS layer-attached laminated resin film, except that each layer in Production Example 3-1 was changed as shown in Table 10 below. A laminated resin film with an HS layer of -8 to 3-20 was obtained.

<Production example 3-7 of laminated resin film with HS layer>
After melt-kneading the resin composition (a) in an extruder set to 230 ° C., it is supplied to an extrusion die set to 250 ° C. and extruded into a sheet, which is cooled to 60 ° C. by a cooling device and unstretched. got a sheet. This non-stretched sheet was heated to 135° C. and stretched 5 times in the longitudinal direction using the difference in peripheral speed of the roll group to obtain a uniaxially stretched sheet. Next, the uniaxially stretched sheet was cooled to 60°C, heated to about 150°C using a tenter oven, stretched 8.5 times in the transverse direction, and then heated to 160°C for heat treatment. Then, the sheet was cooled to 60° C., and the tabs were slit to obtain a biaxially stretched sheet having a thickness of 70 μm.

On the other hand, the resin composition (f) was melt-kneaded in an extruder set at 250° C., extruded into a sheet, and laminated on one side of the biaxially stretched sheet. In parallel, the resin composition (i) is melt-kneaded with an extruder set at 250° C., extruded into a sheet, laminated on the other side of the biaxially stretched sheet, and #150 line gravure embossed. It was led between a shaped metal cooling roll and a matte rubber roll. The embossed pattern was transferred to the thermoplastic resin side while pressing and bonding between the metal cooling roll and the matte rubber roll and cooling to room temperature with the cooling roll to obtain a three-layer laminated sheet. Next, it is cooled to 60 ° C., the edge is slit, and the resin composition of each layer is (f / a / i), the thickness of all layers is 90 μm, the thickness of each layer is (10 μm / 70 μm / 10 μm), and each layer is stretched. A laminated resin film with an HS layer having the number of axes (unstretched/biaxial/unstretched) was obtained.

(Manufacturing of in-mold labels)
<Example 3-1>
The surface of the base layer (that is, the layer formed using the resin composition (g)) of the HS layer-attached laminated resin film of Production Example 3-1 above was subjected to corona discharge treatment under conditions of 30 W min/m ² . After that, the coating liquid (a) for forming a resin film prepared in Preparation Example 1 was applied onto the underlayer by a roll coater so that the thickness after drying was 0.03 μm. The coating film was dried in an oven at 60° C. to form a resin film to obtain an in-mold label of Example 3-1.

<Examples 3-2 to 3-7, 3-9 to 3-13 and Comparative Examples 3-1 to 3-7>
In Example 3-1, Examples 3-2 to 3-3 were prepared in the same manner as in Example 3-1, except that the coating solution for forming the resin film and the thickness of the resin film were changed as shown in Table 10 below. -7, 3-9 to 3-13 and in-mold labels of Comparative Examples 3-1 to 3-7 were obtained.

<Example 3-8>
Both surfaces of the HS layer-attached laminated resin film obtained in Production Example 3-8 were subjected to corona discharge treatment under conditions of 30 W min/m ² , and then the thickness of each surface after drying was 0.03 μm. Then, the resin film-forming coating liquid (a) prepared in Preparation Example 1 was applied by a roll coater. The coating film was dried in an oven at 60° C. to form resin coatings on both sides of the laminated resin film to obtain an in-mold label of Example 3-8.

Table 10 below shows the structure of the in-mold label of each example and comparative example. In addition, the number of stretching axes and the thickness in Table 10 are listed in the order of base layer/substrate/heat seal layer.

(evaluation)
For the in-mold labels obtained in Examples 3-1 to 3-13 and Comparative Examples 3-1 to 3-7, antiblocking property 1, toner transfer property were measured in the same manner as for the recording paper described above. , toner adhesion, abrasion resistance (wet A), and abrasion resistance (wet B) were evaluated. However, printing was performed on the surface (resin film surface) opposite to the heat seal layer forming surface of the in-mold label.

Furthermore, the in-mold labels obtained in Examples 3-1 to 3-13 and Comparative Examples 3-1 to 3-7 were evaluated for printability and in-mold moldability by the following methods.

<Toner adhesion 2>
The printed in-mold label was scratched with a cutter in a grid shape (10 mm wide, 10 mm long) at intervals of 1 mm, immersed in water at 23 ° C. for 24 hours, then removed from the water and lightly wiped with a rag. . 5 minutes after wiping, the adhesive side of cellophane tape (manufactured by Nichiban Co., Ltd., trade name: Cellotape (registered trademark) CT-18) is attached to the printed surface of the in-mold label, and rubbed three times with a finger to ensure sufficient adhesion. Ta. After manually peeling the adhered cellophane tape at a speed of 300 m / min in the direction of 180 degrees, a small general-purpose image analysis device (manufactured by Nireco, model name: LUZEX-AP) was used to check the remaining toner on the in-mold label. rate was calculated. Specifically, an image obtained by photographing the printed surface was subjected to binarization processing, and the ratio of the area occupied by the toner was calculated as the residual ratio. Based on the calculated remaining rate of toner, the adhesion of the toner was ranked according to the following criteria.
◯: Toner residual rate is 90% or more △: Toner residual rate is 70% or more and less than 90% (practical lower limit)
×: Less than 70% residual toner (unsuitable for practical use)

<Scratch resistance: Wet C>
The printed in-mold label was immersed in ethanol at 23° C. for 24 hours, then taken out of the ethanol and lightly wiped off with a waste cloth. 5 minutes after wiping, attach it to a Gakushin type dyeing friction fastness tester (manufactured by Suga Test Instruments Co., Ltd., device name: friction tester II type), and rub it 100 times with a white cotton cloth moistened with water with a load of 500 g. A friction test was performed. The abrasion resistance was evaluated from the percentage of toner remaining on the recording paper after the abrasion test, using the same criteria as in the evaluation of toner adhesion 2 .

<Scratch resistance: wet condition D>
The printed in-mold label was immersed in a neutral detergent (manufactured by Kao Corporation, product name: Cucut) for 24 hours at 23°C, then removed from the detergent, thoroughly washed off with water, and lightly wiped off. . After 5 minutes from wiping, a friction test and evaluation were performed in the same manner as in Scratch Resistance: Wet C.

<Moldability>
The in-mold labels after printing obtained in Examples 3-1 to 3-7 and 3-9 to 3-13 and Comparative Examples 3-1 to 3-7 were cut into rectangles with a width of 60 mm and a length of 110 mm. punched. The processed in-mold label was placed on one side of a blow molding mold capable of molding a bottle with an internal volume of 400 mL so that the heat seal layer faced the cavity side, and was fixed on the mold using suction. Next, between the molds, high density polyethylene (trade name “Novatec HD HB420R”, manufactured by Japan Polyethylene Co., Ltd., MFR (JIS K 7210: 1999) = 0.2 g / 10 minutes, melting peak temperature (JIS K 7121: 2012) = 133°C, crystallization peak temperature (JIS K 7121:2012) = 115°C, density = 0.956 g/cm ³ ) was melted at 170°C and extruded into a parison shape.

After clamping the mold, 4.2 kg/cm ² of compressed air was supplied into the parison. The parison was expanded for 16 seconds to adhere the parison to the mold to form a container, and to fuse the parison and the label. Then, the molding was cooled in the mold and the mold was opened to obtain a labeled container. At this time, the mold cooling temperature was 20° C., and the shot cycle time was 34 seconds/shot. The appearance of the obtained container was visually confirmed and evaluated as follows.
○: Strongly adhered, label lifting cannot be visually recognized △: Label lifting can be visually recognized, but strongly adhered (lower limit for practical use)
×: Peeling of the label or lifting of most of the label can be recognized, and the adhesion is not strong (practical impractical)

On the other hand, the printed in-mold label obtained in Example 3-8 was stamped into a rectangle of 60 mm wide and 80 mm long. The processed in-mold label was placed inside a molding die of a stretch blow molding machine (manufactured by Nissei ASB, machine name: ASB-70DPH) so that the heat seal layer faced the cavity side, and the mold was clamped. . The mold was controlled so that the surface temperature on the cavity side was within the range of 20 to 45°C. On the other hand, a preform made of polyethylene terephthalate resin preheated to 100° C. was introduced between the molds and subjected to stretch blow molding for 1 second under a blow pressure of 5 to 40 kg/cm ² . After that, it was cooled to 50° C. for 15 seconds, and the mold was opened to obtain a container with an in-mold label. The appearance of the obtained containers was evaluated in the same manner as the containers obtained in Examples 3-1 to 3-7 and 3-9 to 3-13 and Comparative Examples 3-1 to 3-7.

<Toner adhesion 3>
The in-mold label surface of the labeled container obtained by the above method was scratched with a cutter, immersed in water at 23°C for 24 hours, and then taken out from the water. After lightly wiping off moisture with a waste cloth, stick the adhesive side of cellophane tape (trade name: Cellotape (registered trademark) CT-18, manufactured by Nichiban Co., Ltd.) on the area that was scratched by the cutter in the direction perpendicular to the direction of the scratch. was rubbed 3 times with and sufficiently adhered. After manually peeling the adhered cellophane tape at a speed of 300 m / min in the direction of 180 degrees, a small general-purpose image analysis device (manufactured by Nireco, model name: LUZEX-AP) was used to check the remaining toner on the in-mold label. rate was calculated. Specifically, an image obtained by photographing the printed surface was subjected to binarization processing, and the ratio of the area occupied by the toner was calculated as the residual ratio. Based on the calculated residual ratio of toner ink, the adhesion of the toner ink was ranked according to the following criteria.
◯: Toner residual rate is 90% or more △: Toner residual rate is 70% or more and less than 90% (practical lower limit)
×: Less than 70% residual toner (unsuitable for practical use)

<Gloss change after molding>
The blank portion of the label portion of the labeled hollow molded container obtained by the above method was measured in accordance with JIS P 8142:1993, and the 75° specular glossiness was calculated from the difference in glossiness of the unformed recording paper. Change in gloss after molding was evaluated according to the following evaluation criteria.
○: Glossiness difference is less than 5% △: Glossiness difference is 5% or more and less than 10% (practical lower limit)
×: Difference in glossiness is 10% or more (not suitable for practical use)

Tables 11 and 12 below show the evaluation results.

As shown in Tables 11 and 12, the in-mold labels of Examples had excellent toner transferability, toner adhesion, and abrasion resistance even when printing was performed by a wet electrophotographic method using a liquid toner. It was also confirmed that the printability was good and the blocking was small. Good results are obtained even under wet conditions, indicating that the film is particularly excellent in water resistance. The resin content in the base material can also be reduced, and the environmental load can be reduced. In addition, excellent in-mold moldability is obtained, with sufficient adhesion to the container even during in-mold molding, and almost no peeling of the print or change in gloss after in-mold molding. According to Example 3-8 in which a resin film was also provided on the heat seal layer side, it can be seen that even a PET resin container is highly suitable for in-mold molding.

On the other hand, when the in-mold label of the comparative example contains olefin copolymer particles, the toner transferability and adhesiveness are obtained, but the adhesiveness is lowered and blocking occurs under wet conditions. Moreover, a resin coating that does not contain a silane coupling agent and a cationic water-soluble polymer does not have sufficient printability.

The recording paper of the present invention is excellent in appearance, and not only has excellent adhesion between the support and the resin film, but also has high adhesion to inks or toners used in various printing methods, especially water-resistant adhesion. , label paper, inkjet recording paper, thermal recording paper, thermal transfer receiving paper, pressure-sensitive transfer recording paper, electrophotographic recording paper, and the like.

The pressure-sensitive adhesive label of the present invention has an excellent appearance, and not only has excellent adhesion between the base material and the resin film, but also has high adhesion to inks or toners of various printing methods, especially water-resistant adhesion. Alternatively, it can be widely used as display labels, tags, etc. for clothing and accessories.

The in-mold label of the present invention has excellent appearance, not only adhesion between the base material and the resin film, but also excellent adhesion to inks or toners of various printing methods, and high water-resistant adhesion. It can be widely used as a label to be provided on the surface of a molded product, for example, a resin container such as a PET resin container or a polyethylene resin container. In particular, it is useful for liquid containers such as beverages, cosmetics, and pharmaceuticals.

1 base material 2 base layer 3 resin coating 4 adhesive layer 5 printing layer 6 heat seal layer 10 recording paper 21 first base layer 22 second base layer 31 resin coating 32 resin coating 40 adhesive labels 50a, 50b in-mold label 101 laminated resin film

Claims (9)

A laminated resin film having a substrate made of a thermoplastic resin film and an underlying layer made of a thermoplastic resin composition disposed on at least one surface of the substrate, and facing the underlying layer of the laminated resin film A recording paper having a resin coating disposed,
The indentation elastic modulus of the underlayer is 50 to 1200 MPa,
The base material contains an inorganic filler, and the content of the inorganic filler in the base material is more than 45% by mass and 80% by mass or less,
The resin coating contains a resin that is a reaction product of a cationic water-soluble polymer and a silane coupling agent,
The content of the silane coupling agent component with respect to 100 parts by mass of the cationic water-soluble polymer component in the resin film is 15 to 60 parts by mass,
The resin coating contains no thermoplastic resin particles,
A recording paper, wherein the content of the inorganic filler is 9 parts by mass or less per 100 parts by mass of the cationic water-soluble polymer component in the resin coating. 2. The recording paper according to claim 1, wherein the cationic water-soluble polymer is a (meth)acrylic polymer or an ethyleneimine polymer having an amino group or an ammonium salt structure. The (meth)acrylic polymer or ethyleneimine polymer having an amino group or an ammonium salt structure has a primary to tertiary amino group or a primary to tertiary ammonium salt structure. 3. The recording paper according to claim 2. The recording paper according to any one of claims 1 to 3, wherein the silane coupling agent is an epoxy silane coupling agent. The recording paper according to any one of claims 1 to 4, wherein the resin coating has a thickness of 0.01 to 5 µm. A method for producing a recording paper having a resin coating on a laminated resin film,
The laminated resin film has a substrate made of a thermoplastic resin film and a base layer made of a thermoplastic resin composition disposed on at least one surface of the substrate,
The indentation elastic modulus of the underlayer is 50 to 1200 MPa,
The base material contains an inorganic filler, and the content of the inorganic filler in the base material is more than 45% by mass and 80% by mass or less,
An aqueous solution containing a cationic water-soluble polymer and a silane coupling agent, containing no thermoplastic resin particles, and having an inorganic filler content of 9 parts by mass or less with respect to 100 parts by mass of the cationic water-soluble polymer. A method for producing a recording paper, characterized in that the resin film is formed on the laminated resin film by coating on the underlayer and then drying. A substrate made of a thermoplastic resin film, a first underlayer made of a thermoplastic resin composition arranged on one surface of the substrate, and a thermoplastic resin composition arranged on the other surface of the substrate. A laminated resin film having a second underlayer,
a resin coating disposed facing the first underlayer of the laminated resin film;
and a resin coating disposed facing the second underlayer of the laminated resin film; An adhesive label having an adhesive layer that
The indentation elastic modulus of the first underlayer and the second underlayer is 50 to 1200 MPa,
The base material contains an inorganic filler, and the content of the inorganic filler in the base material is more than 45% by mass and 80% by mass or less,
The resin coating contains a resin that is a reaction product of a cationic water-soluble polymer and a silane coupling agent,
The content of the silane coupling agent component with respect to 100 parts by mass of the cationic water-soluble polymer component in the resin film is 15 to 60 parts by mass,
The resin coating contains no thermoplastic resin particles,
A pressure-sensitive adhesive label, wherein the content of the inorganic filler is 9 parts by mass or less with respect to 100 parts by mass of the cationic water-soluble polymer component in the resin coating. An in-mold label in which a heat seal layer is provided on one surface of a laminated resin film,
Having a resin coating provided on the surface opposite to the heat seal layer of the laminated resin film,
The laminated resin film has a substrate made of a thermoplastic resin film, and a base layer made of a thermoplastic resin composition provided between the substrate and the resin coating,
The indentation elastic modulus of the underlayer is 50 to 1200 MPa,
The base material contains an inorganic filler, and the content of the inorganic filler in the base material is more than 45% by mass and 80% by mass or less,
The resin coating contains a resin that is a reaction product of a cationic water-soluble polymer and a silane coupling agent,
The content of the silane coupling agent component with respect to 100 parts by mass of the cationic water-soluble polymer component in the resin film is 15 to 60 parts by mass,
The resin coating contains no thermoplastic resin particles,
An in-mold label, wherein the content of the inorganic filler is 9 parts by mass or less with respect to 100 parts by mass of the cationic water-soluble polymer component in the resin coating. further comprising a resin coating provided on the surface of the heat seal layer opposite to the laminated resin film,
The resin coating contains a resin that is a reaction product of a cationic water-soluble polymer and a silane coupling agent,
The content of the silane coupling agent component with respect to 100 parts by mass of the cationic water-soluble polymer component in the resin film is 15 to 60 parts by mass,
The resin coating contains no thermoplastic resin particles,
9. The in-mold label according to claim 8, wherein the content of the inorganic filler with respect to 100 parts by mass of the cationic water-soluble polymer component in the resin coating is 9 parts by mass or less.

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